depends on what you want out of 'visit'.
You going to learn or just to tourist around?
I took an educational program through
http://www.nrcsa.com , cost me about 10k ... airfare through Japan Airlines was $800 round trip.
but those 10k included stay with a host family, books, tuition and 2 meals and transportation to and from house/school for THREE MONTHS.
Classes were 5 days of the week mo-fri 8 to 4 pm, the friday class was a 'culture' class, which really was field trips to theatres, temples, etc etc. the other 4 classes were language classes.
I really enjoyed my stay, even though the language classes were a waste of time since the 'immersion' method they used to teach just didnt work for me... but man, just staying with the family, the trips, the weekends i spent 'exploring' were really worth it.
If you want to go to just tourist around, be prepared to pay around 100 bucks per day with no meals for a hostel (not hotel, not motel, hostels there are just places you go to sleep in, they basically give you a 'traditional' room which is the size of 1 room, with a communal shower/bathroom (some are nice and have a hot water tub... so i suggest you 'bathe' at 11pm to avoid sharing the tub with 10 other guys)
Food there is relatively cheap. That impressed me. I could buy a bento (lunchbox) on a store that had a lot of food (sushi, rice, vegetables, fish, meat) for about $3 dollars worth... fruit juices were cheaper than sodas...and much better (and sold in vending machines)... milk IS expensive (like 8 bucks for a small half liter of milk).
Travel is expensive for the foreigner, train tickets cost $10 one way.. so be prepared to spend at least 80 bucks a day on just transport. OR be wise and buy a Japan Rail Pass before entering Japan (sold at travel agencies, or you can get it direct through Japan Airlines)... costs you like 700 bucks but it gives you total access to any train, anywhere, any time. You can even go from city to city with it at no cost (and those train tickets alone cost like 200 bucks). And they expire 2 months after you buy them, so its REALLY worth it. And trains are THE way to get around there, if you get a taxi (or rent a car, which i really dont suggest.. roads there are extremely narrow.. i think only a british person could drive ok in japan... until he meets the kamikaze taxi drivers (really, thats how they call them there in Japan) that drive like madmen).
Be sure to get the travel agency to do some research into local festivals and events for you. I was lucky the school i went to did that for me... i was honored to be able to see one of their puppet-theatre living legends perform, i was able to see the winner of the sumo tournament train in his dojo (stable they call it i think)...the hawaiian guy (i went there in 99)... and attended local festivities in the temples (horse mounted archer competitions, Bon dancing, etc). This is REALLY important, if you just go there and stare at the big super commercial city, you will miss the best stuff about japan.
also make sure to learn a few phrases and customs.. and get used to traveling without bulky items, for the place is an anthill of people, you will never get 'personal space' ... and you will want to be able to ask how to get to places (unless you can read kanji... almost everything in the big cities is in Hiragana/Katakana/Kanji with english translation below it, but as you leave the immediate center of the city this stops... so if you go to mt. fuji and just walk around the town, the moment you step off 'tourist lane' you will not be able to read the street signs).
Wish i could go back for a year this time... awesome place. Just need to win the lotto.
or hey, take me as a guide
