[vulgarshudder]

Uh you don't always get host familys for university study abroad programs. If there is, it's usually short term (6 weeks), and optional. I didn't bother looking into it, I value my independence too much.

You will be an exchange student with a university which your university has an agreement with. You go there, and someone from there comes to your uni in that year.

The idea is to further your japanese...what the classes are like will depend on the university. Some unis have very tough intensive programes...some you turn up you get a B, you hand some work you get an A. But to be honest it won't be the classroom you'll be learning the most japanese, it'll be outside actually using your japanese. But that'll depend on what the foriegner community is like at the uni and how determined you are. I knew people who went to waseda, which has ALOT of foriegners and classes in english
where as I went to a uni that had 2 other white people that year and ALL my classes were in Japanese. I admit I goofed off a bit class wise, but I hung out alot more with japanese people and to this day my speaking and listening are still better than the waseda people.

The university should sort out everything, you fill in application forms (how long these are or if there's a medical depends on the uni) send them to them, and they send you your certificate of eligibility for the visa.

The university will arrange accomadation for you, a dormitry.