If you on a budget or even if you are not, the 100 yen shop is where you sshould be heading. You can get a range of great Japanese stuff which can double up as sovenirs. From Travel goods to stickers, from slippers to toys the 100 yen has it all. Main store is Daiso there are stores in virtually every city. The flagship store being in Takeshita Dori in Harajuku.
[youtube:http://www.youtube.com/watch?v=5Mxc0NO_zwE]