Used Good

What are good used video game stores in Japan?

I am traveling to Japan this fall. I was wondering if people could suggest good places to buy used video games. I know places like Super Potato and Book Off. Any more places, and their location would be appreciated. Tokyo area is preferred; however, I will be traveling around so other locations are great.
Would any one of these Book Off, Geo, etc. be better in prices? Or have good deals. I would like to get some PS3/PSP games for cheap (at least cheaper than the new Japanese price.)

There are so many used video game stores in Japan. GEO is a national chain with a lot of stores across Japan.

You can go to Akihabara, the town of game and other stuffs and you will see a bunch of used game stores.

Toby Keith – As Good As I Once Was