As you may know, dear friends, I am in love with Japanese paper. There are scores of paper choices not available to us here in the US, and my dream is to visit Japan to satisfy my paper cravings. Here are links to some of the stores I've found online that look absolutely wonderful; now all I have to do is make a plan, and I am there! (Note: these are mostly review links, as they are written in English.)
Yanaka: Isetatsu Paper Store
(at 5:33 in the video)
Tokyo: Ozi Washi
Osaka: Winged Wheel Stationery
Are there stores you love that I've missed? I want to find them too, in my travels -- let me know @papertraveler.