One of these links will get you what you are looking for during the short time you are in Japan. No guarantor is the key to a successful search for a non-Japanese renting here and for anyone living for less than a two year period.

http://www.tokyoapt.com/

http://www.tokyoapartments.jp/

http://www.japan-guide.com/e/e2207.html

Have a look at those links and also be sure to keep my e-mail handy for questions offline and after you arrive. You can reach me initially through PM on FT.

I live here, work in the area you describe, know the TUJ people in fact, and any FTer in need is always welcome to contact for info and a cold beer or several.

Mike