Hello Rita,
Using the German phone book it seems they are all over Germany.
Yes and no - I found most Postal-zip-codes beginning with 3...., and I saw
all numbers from 0.... to 7.... - but no one beginning with a 8.... or
9.... - with other words your Gieselmann came probably from nothern Germany
and not southern Germany - and Munich (M�nchen) has numbers beginning with
8.... ( I did not look on all of the 588 - only the first half of them)
I do not know a lot about ancestry-research in Westphalia (Westfalen) - but
if you have to search in the Rhineland (Rheinland) - there exists a CD about
the emmigrants. (Auswanderer CD) I don`t have this CD - and I don`t know
the time period - but if you have luck you may get help from the list.
Greetings from Munich
Christine