I managed to spend a day at Maiko Snow Resort in Niigata for some snowboarding. It’s a nice place if you’re out for a day trip as the ski centre has everything you would need in one building. You can ride the gondola and hit the slopes almost right after you walk out of the locker room. There’s a hotel about 10min by car or bus from the ski centre if you choose to stay the night.
Not a bad place for kids too.
More information at http://www.centleisure-maiko.com/