When I should be doing other things, I like to look at camera gear. I just found Camerafan which makes the whole joyous slog of looking at classic camera gear a whole lot easier.
It is a Japanese site that has listing for a lot, if not all, second hand camera stores that sell online in Japan. This saves me from dead-links and awkward page searches. Some shops have definitely got better search features on their pages tan others. With this site, you can enter some basic parameters and it gives search results from several different stores. Oooh, lovely! Comparison shopping made easy! You do need to be able to speak and read some Japanese.
My favorite second hand camera shop in Tokyo is Map Camera.I find them consistent and really reliable in assessing the quality of the gear they sell. They tend not to have super-obscure B-class cameras and that is what I have developed a passion for ever since I bought my Petri 1.9 rangefinder.
Here is a link to the Petri cameras that show up from a search on Camera fan. No cameras similar to mine available… nanninannibooboo!