Have you checked out Baring-Gould's Annotated Sherlock Holmes? It's just chock full of odds and ends.
No, but I promise that I will. FYI, I've got a list of over 200 books that I've used for references and background, including all of the Arthur Conan Doyle books, of course.
A German Sherlock Holmes . . . . ? Hmmm . . . THAT is an odd thought. Do Germans tolerate the sort of eccentricities that Holmes cultivated? Maybe among the nobility . . . it's an interesting idea.
True, Holmes doesn't sound like a stiff-necked Prussian or NordDeutscher, but that's not quite the direction I've gone in; I've postulated him as an Austrian/Bavarian veteran of the First World War, disgusted with German politics and the nationalism that got so many of his fellow soldiers killed. On a disability pension from the war, he lives with his wife and reads, a particular fan of the Holmes novels, and follows in the British consulting detective's footsteps; I'm even playing with the idea of having an aging Dr. Watson turn over his old crumbling files and notes on the late Holmes' unfinished cases to The German Detective. We'll see.
Yeah, I could see one of the "kleine diebische Bergvolk" as a Holmes type. Bavarians are pretty neat people. I think of them as good-old-boys in Lederhosen and we get along just fine. They haven't discovered the wonders of the pickup truck yet, but they do have a proper appreciation for good hunting dogs and good beer! (and I must say your average Bayerischer Kerl has a better taste in beer than your average Bud-drinking good old boy!)