Dear sirs, I am working on an "Ahnentafel"of my grandsons and one of their forefathers Johann Heinrich Redeke. He was born in Diepholz on 3-1-1840. His parents are named Heinrich Ludwig Redeke and Johanna Charlotte Bergmann.
Can I join the "Liste" and try to obtain information about the latter persons and their forefathers? Or are there formalities to fulfill? Yours, Peter Mouton.
Hi Dr. Mouton:
Since your message made the list, it appears that you are now a list member. Welcom aboard!
The Mormons/LDS/Family History Center at the URL
http://www.familysearch.org/Eng/Library/FHLC/frameset_fhlc.asp
has the following information for Diepholz:
Germany, Preu�en, Hannover, Diepholz - Archives and libraries - Inventories, registers, catalogs
Germany, Preu�en, Hannover, Diepholz - Census
Germany, Preu�en, Hannover, Diepholz - Civil registration
Germany, Preu�en, Hannover, Diepholz - Colonization
Germany, Preu�en, Hannover, Diepholz - Court records
Germany, Preu�en, Hannover, Diepholz - Emigration and immigration
Germany, Preu�en, Hannover, Diepholz - Genealogy
Germany, Preu�en, Hannover, Diepholz - Historical geography
Germany, Preu�en, Hannover, Diepholz - History - Sources
Germany, Preu�en, Hannover, Diepholz - Jewish history
Germany, Preu�en, Hannover, Diepholz - Jewish records
Germany, Preu�en, Hannover, Diepholz - Names, Geographical - Indexes
Germany, Preu�en, Hannover, Diepholz - Naturalization and citizenship
Also, much more information may be availabile if you could provide more information. Did they go to another country? Where do/did more recent ancestors live? There could be ships logs/manifests, census records and so fourth.
Gale
Welcome aboard Peter. You are indeed a practicing Mitglied auf Lebenszeit of our Kuhdorf (assuming you've subscribed to it for the long haul). Remember to keep your membership card handy in case you need to get through the door when the server overheats (normally during the holiday periods, or when Jb goes on vacation). 
It might be helpful to know how much experience you have here in digging up old bones. One of the unfortunate but inevitable things associated with mailing lists like these is that one is never sure if new members (or existing members for that matter) are old hands or just mildly experienced, or perhaps brand new to the sport, unless it is stated up front. Many times you give out advice based on a certain query or "feeler" only to find out soon enough the seeker has years of experience behind them, and therefore is looking for rather specific information only. Other times it is just the opposite. You dish out suggestions assuming the inquirer already knows the basic staples of genealogical research, along with the various acronyms (net lingo) commonly used on interactive lists. Soon you see a return response along the lines resembling "Sorry, but what's that?"
Therefore if you could provide a brief idea of how much effort you've expended to date, and how far you've gone or progressed by way of your searches, you'll invariably stand a better chance to get something helpful in return. This is particularly apropos for those just starting their journey into their family past.
Now that's not to say an old dog can't learn something new. The fact is, it happens all the time. H-L is living proof.
Jb
Peter I didn't forgot you. Seeing that your Ahnentafel is now comprised of 1100+ persons, to include 12 sets of forebears in Germany, I'd say you have your work cut out for you filling in dates and places. Your genealogical efforts to date prove you are well versed in this pasttime, and should have no problem fitting in on the list. But old hand or new, there is always something new to be found -- and learned.
As for the direction of your quest, I'm not sure we're equipped to help directly with your rather sizable Ahnentafel, but we can certainly be of assistance in plenty of indirect ways [assuming we agree that the Lord helps those who help themselves]. If you haven't gathered as much so far, this list is basically a bilingual sounding board for those interested in furthering their Hannoverian-based family trees. The means by which this is accomplished is as varied and numerous as the list membership itself, and since there is no magic bullet to genealogical success (short of patience, effort and a fair sprinkling of pain), it often takes the contributions of the collective to help stitch together the pieces of the research puzzle. The farther we move from our own shores and onto foreign ground, the more this is felt.
If nothing else, Hannover-L is a learning center where tips, techniques and suggestions are distributed freely, and with a modicum of effort, applied on a personal level. These "tools" and tips come both from the Anglo and German side of the lake. But a few basics are always worth mentioning right off. For starters, one simply MUST do as much homework as possible on the "English" (= non-German) side as possible, to maximize successful returns from the German end. This includes background research on the ancestral line(s) in question - the more methodical the better - and the tapping of as many available resources on this side as possible.
The LDS FHC online catalog is a great starting point; however the COMPLETE cataloging found at the FHC centers themselves is better suited for deeper explorations. Many Lower Saxony based records have been microfilmed over the years and are now part of the LDS organization's massive film and fiche collection. Understandably, substantial gaps in these holdings exist, and some regions (and record types) are better covered than others. Only way to find out how it might apply to yours is to dig in and take an in depth look for yourself.
From the German side you have various archives, both church and civil, that
can be tapped, either by visiting in person or via correspondence. The latter approach is generally slow though, due to those institutions' resources being tapped to the max. The Germans also have rather strict privacy laws in place, something ironically they're looking more and more to loosen up a bit while we - as Americans at least, in the "land of the free" <g> - continue to ramp ours up. I live in the state that once led the way in open record access, but now leads it in draconian like encroachments, all thanks to a handful of criminal twits who we must all be "protected" from at this late point. In any case, suffice to say that LDS has done a commendable job in filming as many records as they can from the German end, and only a fool would pester our Germans cousins before fully exploring what LDS has in its holdings stateside.
The other obvious angle of attack is per the enlistment of a professional researcher, but most of this won't come cheap (good things rarely do though). Naturally this comes down to what funds you have available to expend versus how much you feel you can - or prefer to - accomplish on your own. There is no "one shoe fits all" solution here - to each their own. I can say in a rather generic way that the average Yank might stand a slightly better chance of walking into a local city or county or even state archive and finding open access to most of the repository's holdings than say the average German in their country, but again, that's using a broad brush.
In Germany, noting that many exceptions will and do occur, more tend to rely on professional researches to do these sort of things, simply because the records are often scattered all over the place and the pros are best versed at knowing where to look, and interpreting properly what they find. The aforementioned privacy laws are not always easy to work around either, and it goes without saying, well credentialed pros are better suited to interact with the local archivists. But that said, both German citizens and visiting foreigners are allowed access to most archival collections and repositories there, only the thought of asking Herr or Frau Schmidt to run down to the local church or city archive "to have a quick peek" isn't as common a scenario or feat as we sometimes might expect to see in the States.
We also have an ever-expanding list archive that can be quite helpful when searched wisely. Simply employ the appropriate search terms, frame it by dates if desired, and away you go. Everything that gets posted gets archived permanently (so be careful what you blurt forth lol), and this will no doubt be a boon to future members of the list who tap it, assuming GenNet doesn't pack it up and call it quits at some point. [Not to worry there though, those sucking sounds you sometimes hear are the vacuums owned by Ancestry.com that never miss a morsel or opportunity to expand]
Our list administrator is the low key but very capable Juergen Drees from Braunschweig, known for his judicious use of the spray bottle to keep the list server cool and burp free. Fred Rump (alias the Rumpster, Big Daddy, Curmudgeon in Chief, the Mad Mot�rhead, the Jersey City Bomber <invent your own and add freely>) is the patriarch of the list, who not only visits on occasion to make sure we minions are remaining active and accounted for, but put H-L on the map to begin with -- in more ways than one. He also was instrumental in creating a number of other German GenNet lists, and remains the List Papa in both spirit and deed. When he's not preoccupied traveling the country (often spotted near Disney World on, uh hum, bald tires), he'll stop in to speak his mind, then disappear like a shadow in the night. Not to worry though, his more recent alusiveness is certainly compensated by his astute and insightful contributions as evidenced in the list archive.
If one of the various Barbara's on the list spot something interesting, they're sure to post it - keep your eyes peeled there. I could name all kinds of helpful folks, on both sides of the pond, but in reality, the list would be too long. Even those with just occasional chip-ins often cast pearls. We also have a number of professional researchers, historians, old hands and even a writer or two as members, and this from areas all over the globe. I think it is fair to say that those who derive the most from a forum like this are those who came for the long haul, and not a quick fix.
As on every list, things can sometimes get a bit redundant, other times ho-hum quiet, and now and then controversies arise like we witness in every other facet of our lives, but over the long run - assuming you can manage to grin and bear it - you WILL learn a lot. The collective inputs, the ebb and flow of ideas and research approaches, the spirit of the "Kuhdorf" as one lister so wistfully termed it, guarantees as much. You only have to speak up or inquire, and who knows what may follow.
Speaking of the Kuhdorf, I was digging through the archives in some uncharted areas recently and unearthed this private rumination like between Karl and Hans. Amazing what you can find between the cracks when you dig deep enough.
K: Wish more of the Americans could speak Deutsch .. would even things up a bit in our little Kuhdorf.
H: Well at least we are improving our English, I mean, don't you think so?
K: Ja vielleicht. Only I fear we are learning mostly American Mischmasch, you know, the stuff some call 'Polyglotten Sprache'. When I try to follow JB's spiels, I find myself reaching for the aspirin bottle.
H: Yes yes, I know what you mean. That's why I'm putting my faith in Rena these days. They say she speaks Oxfordian so that should help me thinks. I sure hope she isn't Cornwallian Welsh or we're sunk.
K: They say there's a lot of Saxon cast-offs in Liverpool... you don't think ...
H: No chance!
K: Ok that's good to know. Yeah I hear she's some kind of royalty, true blue as the Yanks say.
H: The King's Legion kind at least. Possibly more...
K: ah.. there may be hope.
<snip>
Ok enough. Hope that provides a satisfactory overview. It's Ultimate Fighter time for yours truly. Someone's gonna get themselves black and blue MMA style, I can feel it. Yeehaw. 
Jb
PS. Since you stated earlier that your forefather Johann Redeke was born in Diepholz in 1840, you might want to tap Falk Lebezeit - Mitglied auch - who is a professional researcher out of that same city, and a very capable one at that. He might well give you a few insights and maybe a touch of consultancy, assuming you're willing to make it worth his time. The pros on the list, while very helpful with their varied contributions, also have livings to make doing these tasks. Having said that, remember everything stated above applies equally so, and a lot of it costs only the time and effort you're able to devote towards it.