Interesting thread. I'll add a few.
Alan Shaw, md of Harbeth Audio (I think that's their name now).
Alastair Gardner, proprietor of Signals in England. Alastair sells Harbeth loudspeakers over the web and a lot of other stuff and gives great advice and handholding. Welcome to stay at my house anytime he comes to Southern Cal.
Ray Kimber (not a recommendation of his products (good stuff - just don't know what anyone might be comparing it to) just that he's a really good guy.
Jeff Joseph (ditto).
Everyone at Reference Audio Video.
One of my favorites, no longer in business in SoCal, Mel Murakami. I think he moved to New York.