Hi Faye!
LDS church has (http://www.familysearch.org/)
CARL DIDERICH LUCAS VON OVEN
*07.03.1825 Bockhorn
+ 25.06.1869
parents: Hermann Gerhard von Oven and Susanna Alida Kolff
This could be a brother of Hermine Suanna Wilhelmine von Oven.
So your Hermine is from Bockhorn.
A listing of all church books from the Grand Duchy of Oldenburg you find here: http://www.genealogienetz.de/vereine/OGF/index.html
Click "Kirchspielverzeichnis" and you will find Bockhorn and where you can loop up the church books.
Greetings from Schwaben,
Andrea Korbanka