http://www.popjapantravel.com/tours/24/Iron_Chef_Tour_2...it is an iron chef tour, but thier should be some free time to explore tokyo.
http://www.intermixi.com/w/?page_id=8
they are doing a tour of tokyo, tokyo game show and possible to extend to kansai, aka osaka, kyoto. not alot of info as of yet
it is in september tho.
there are a few other tours but i am unfamiliar with them.