sch, when are you going to japan? here's my guide to tokyo..
okachimachi (accessible by JR Yamanote line) - place to stock up snacks. once you exit the train station, you should see a traffic light crossing. do not cross and turn to your right and walk. walk all the way down n u will see another traffic light crossing. in front of there is a big purple building called takeya. that is 1 place to get the stuff. i usually get my milk tea from there. next, still remb tat traffic light crossing at the train station? cross that and walk straight into the lane. you can slowly shop there. some stalls even sell fresh seafood like salmon. looks damn fresh. at the first turn on your left, turn left. then you will see a few shops down the road is the snacks shop. next to it is a tiny shrine which is barely noticable. that is shop no 2 you can get your snacks n sauces. i even bgt instant noodles back coz it is so much cheaper.. in sg, it cost more than double the price i think. in okachimachi, you will see a few shops whereby it has a vending machine for food. quite cheap n nice. there is one shop i always patronize but very difficult to describe to you.
i think there is no need to introduce shibuya, shinjuku and harajuku to you right?
there is this ramen chain store that is very famous and yummy. Jangara ramen. you can even request for english menu. they have branches in ginza, harajuku, akihabara. go to the one at harajuku coz it is easier to find. i tried at ginza and harajuku. ginza branch really takes time and effort to locate the shop.
http://www.kyusyujangara.co.jp/
in shibuya, there is this sushi conveyor shop whereby everything cost 100 yen per plate. however, min requirement is must eat 7 plates within 20-30mins. n you must order in japanese with the chefs. n if you feel rich, do check out one of those more authentic sushi restaurants. the cut of the fish, texture, freshness is very different from what you get from 100yen sushi shop.
n do try the onigiri at convenience stores. it taste much better than what you get in SG.
then there is this fish market called tsukiji fish market. must go damn early like 7am. you will get to see the auction of fishes. this is only available til end of this yr. something to do with their govt regulations. but the sushi sold there is bagus! oishiii.. yummy..