Possible that they married in Sudlohn ofcourse ,
you could mail to the archiv Sudlohn/Oeding, I was very well helped there. If German language is too difficult, English will be understand too I assume.
website : http://www.suedlohn.de/
Or you can try by posting your question on the German Message Boards,
always mention the religion the family had -if you know.
Then another option: there is a German Genelogie Forum on http://forum.genealogy.net/
that's in German, but English language will be understand also perhaps, you will to have log in with a mailadres and password.
Then go to Regional and choose for Nordrhein Westfalen, Sudlohn is in this state.