So, you have decided, for whatever reason, that you want to come to this country. Well, I would strongly advise you to stop and think about exactly why, or rather, for what purpose.
There are roughly 4 main groups that you can divide yourself into.
1 Tourist You are just planning on staying in Japan for a few weeks to a few months
2 Work You are planning on coming to Japan, and staying here for roughly 1-5 years
3 Live You are planning on staying here for as long as you can
4 Expat Your company is going to pay you a bazzillion bucks and give you a free apartment
So, which ever group you are in, I will explain that to do next week.
Until then, stay frosty.