During the next couple of months, I will try to add entries of all official german CoC publications into the wiki. This will take time and updates might be as sparse as one every other week or so.
Nonetheless if you ever wondered what german titles have been published (and what horrors hide behind that 'awful german language') make sure to monitor this thread, as I will post updates in here as well.
Feedback is highly appreciated (I'm new at this ).
To start this endeavour, I have added the oldest and the newst title.
Auf Cthulhus Spur (1986)
Die Janus-Gesellschaft (2013)
Oh and if you are interested in any particular titles and want to see them added sooner rather then later, let me know.