Best Audio store in Tokyo ?

Just go to the Akihabara area of Tokyo, you will be amazed at the range of high end HiFi and HT equipment on sale at many stores in this area. Go to this site for more information:

http://www.japan-guide.com/e/e3003.html

Akhibara's a waste of time today, almost all the high end and vintage dealers are gone, what remains are tourist traps catering to lower end regional travelers or anime themed stores selling colectable trash to adults. Your best bet is to buy a recent copy of Stereo Sound or some other audio rag and look through the store ads.