You can enter on the tourist visa and find a job at which point your employer will do the application for change of visa status. The trouble about doing it in this manner is that you will need the funds to feed and house yourself till you find a job.

As far as cultural visa for doing karate, I have no idea. I would assume that you are going to find a school before coming over so I would put the question to them.

Also you can do what some people who's tourist visa is about to expire and make a short trip to South Korea. That way when you re-enter Japan you are granted another tourist visa. But I am unsure about the legality of such a move even though I know it has been done before.

In South Korea this is what is known as a visa run. People are hired in South Korea but technically the work visa cannot be granted within S. Korea so they have to run to Tokyo for like a two week vacation to get the paper work done.

Hm, I was hoping I'd be able to get in on a student visa. (However, my school keeps jerking me around, so I no longer consider them a reliable method of getting to Japan.) Maybe I'll get lucky and when it comes time to get my visa, someone will have a solution to my problem. Heck, maybe there's a company that can help. As I said, the only agency I know about requires you to already be in Japan. :P

Thank you for all your help though!