Wah xunjas, since when u got 3 70-200s?? U seemed to be a 70-200 fan.
Canon EOS 5D, 24-70 f/4 L IS, 50 f/1.2 L, 70-300 f/4-5.6 L IS, 600EX-RT. Sigma 12-24 f/4.5-5.6 EX.
At least a big shop like yodobashi has a reputation to uphold.
I posted my recent experience of buying a lens in Tokyo here
Only got one lens in Tokyo, coz that's all I needed. :-)
I could have gone looking for the shop with the cheapest price, but heck, the difference between kakaku and their price might juz be 500Y (~SGD$7-8?) might as well spend the time walking around tokyo with the new lens rather than looking for a shop. Moreover, I don't read Japanese, so .. harder to get around.
In Tokyo, might want to try Shinjuku area (both east and West exit) they have 3 big shops that you can patronize: Yodobashi, Bic Camera, Sakuraya. All have salesman with acceptable English. If you print out the model number or picture of the item you're looking for, it might be easier to talk to them.
Ikebukuro area also has lots of Bic Camera shops, first floor always has DSLR stuffs.
I feel that the price of their (JP) camera body and lenses are quite cheap, can't say the same abt their accessories though. SG seems to have abt the same price.
However, I was rather biased, only looking and comparing alpha systems accessories.
hope that helps