Kiddy Land - started off as a small book shop in Harajuku Omotesando during 1950 and grew over time to be the largest chain of toy and novelty goods stores in Japan.
When I first visited Tokyo, friends would recommend Kiddy Land as a place to visit where I would pick up a load of novelty goods to bring back to the UK.
The closest stations to Kiddy Land is Harajuku or Meiji Jingu Mae.
Address : 東京都渋谷区 神宮前6-1-9
Map : http://ow.ly/2jmwy
The current building will be completely dismantled and replaced by a spanking new store in 2012. In the time being Kiddy Land will move about 150 meters down the same road towards Shibuya from mid September.
Most of the stuff in Kiddy Land however is mainstream goodies - meaning that if you are looking for a load of K-ON! or other anime stuff then you probably want to spend your time in Akihabara instead.