No, there should be a complementary German deck on Tinycards (just checked what it's called). At least I've got it (although I haven't done anything with it)... Of course I'm not really recommending it (since I haven't used it myself).

On the topic of books, I surprisingly managed to find a lot of free study materials for a non-language-related topic that I want to learn. I almost gave up on it because all the decent books seem to be at least $20, everything below is filled with typos and in general low quality... And then somehow (after a lot of googling) I ended up on top of a heap of free quality introductions... Plus a couple book drafts (which I don't know if the author is that generous or forgot to take them offline).

That is all to say that I'm suddenly much more optimistic about human generosity in this area. I hope it turns out similarly for you with German... Well, and for me with Welsh, eventually.