Private Exchange Program?

I was curious about the possibility of exchange programs between Japan and the U.S. I can not seem to find sufficient enough information regarding this and I am not even sure if they are available to someone no longer in school such as myself. What I would ideally like to find is someone living in Japan that could be a penpal for a while, opening up the possibility of mutual travel assistance in the future. I am 23 years old and I live in Oregon and would love to show anyone from Japan around my great state if they were interested, providing a place to stay, a means of traveling around and any other living assistance that would provide helpful to another tourist such as myself. With the hope that in return, I would be allowed to travel to Japan to visit them with similar accomodations. If anyone knows of a good place to meet someone that may be interested in a deal like this, or programs that deal with what I am looking for, any and all information is greatly appreciated.

Thank you.
Acal

I recall a friend of mine telling me about a website that arranges a network of "couch surfing," where precisely that sort of situation gets set up. They were talking about Europe mostly, but it seems that there's a great deal of "couches" in Japan. Check it out for more info.

Couchsurfing

thanks a ton! thats an awesome site.. if any others know of good places to meet penpals and whatnot let me know.. thanks again for the reply.