Only folks I know of are In Lindlar, bout 250 K's north of you. I'd do a search of the members and look for German based ones.
Go to member info, member list, over on the right hand side, Search members and select Advanced, and in the Country add Germany. You might want to do a couple of searches, and some will have written Deutschland which won't show as part of a Germany search, then drop them a PM.
Most will understand some English, being a member of this board.
You will need good German skills, but perhaps you can get help, Link to German LT site/forum.
On the site thay have listed 4 Stammtische (Top Table, or Regular's Table) I guess it's a Club/Group, anyway. 4 Listed,
Lindlar, Münster, Ost (east - not populated) and Süd (south)
There is a Kontact (no translation required) try dropping them a line. If you get completly stuck, we have better German speakers than me on here, who would probably help, and will correct anything I've got wrong.
You might also post in the Europe Section, I know at least 1 guy Hartmut, looks in there, but he only posts in German, but can read English OK.