Accommodation - Hotel, Ryokan -
Good news for all inbound tourons is that there’s plenty. Bad news is that it can all be often booked up well in advance, especially over the peak seasons (National Holidays & long weekends especially), but also through the hiking season & festivals (Saito Kinen in particular). I suggest you book ahead to avoid disappointment, online probably better than by phone if you don't speak Japanese for most places.
Accommodation has been set out here geographically. There are upmarket hotels & Japanese-style “Ryokan”, business (Y4,000 - Y6,000) & budget variety too. (What is a ryokan you ask? http://www.ryokan.or.jp/index_en.html and I’m glad you asked!) Something for everyone & all pockets.
There are a number of European-style "Pension" in & around the ski hills, which tend to offer friendly family orientated service. There’s even a YHA.
There are a number of options for the outdoorsy types, with a brief listing here of official campsites. In the unofficial category? Well, quite a lot of travel stories I hear suggest finding a park & setting up late, leaving early. As long as you don’t make a mess or a racket, I don’t think you’d be bothering anyone in Agata-no-Mori, or along the Susuki River (even better as you’d be able to have a BBQ & not worry the neighbours) not a million miles from Matsusho HS. Just a thought!
Enjoy your stay, please post your reviews of where you stayed, and remember to come back with your friends!
All rates quoted are for one single room in hotels/downtown ryokan/"pension". All other rates (for non-downtown ryokan, Kamikochi hotels/lodges etc) are for one person + dinner & breakfast.
Please post your reviews of these ryokan in Guest's Blog, especially how easy they are to book if you don't speak Japanese. Comments on the food and bathing facilities please.
You can also search for hotels and ryokans with the hotel/ryokan/tour booking site JAPANiCAN.com.