There's a lot of places to stay, and for some reason Hotels etc. Are really cheap like the most expensive one i found when i was over their last time was about $120 a night. But it really depends where you are going. First its going to be a massive culture shock when you arrive at the airport you will have no idea my suggestion is find the nearest info booth in the airport and get them to direct you to a hotel booking service for the night then once you have that hotel booked find out where it is (will usually be near popular area's) and catch the nearest train/subway to it.
After the first night you will usually get your bearings make sure you have a little phrase book or something like that so you can ask basic questions. Best thing to do is find the nearest internet cafe and search for where you want to go and what you want to do. (theres an internet cafe pretty much every block or area so you shouldn't have trouble finding one) So once you figured out what yah wanna do just print out a map. Or if you feel like chillin' in the town a bit just print off a local map or goto a convience store and find one.
It's always fun just to see whats around cause you can end up in all kind's of adventures. Last time me and my friend just flew into kansai airport conviently met up with an aussie like us who had been to the country before and helped us out at the start because we were just dumbfounded.
But also if your ever in Kyoto, Look for Kyoto's Cheapest Inn its 200 yen for a week. Which is about $20 converted
. Though its not very private not many hostels are but you get shower's, Bike Hire, Laundry Services and free internet :P. I couldn't be bothered typing out the rest it's best once your started to find your own way cause thats how you end up having the funnest time