I'm looking for partners do hopefully do some ice/mixed/mountaineering type stuff from 22nd March to 6th April, probably in the north Alps, but I'm based in Sendai so I can head wherever. Got a sparse-ish trad/ice rack and 9mm 60m single/half rope with me. Any advice about where to go etc would be appreciated as well.........its a pain in the arse finding any info when you don't read Japanese!
Try the below book for objectives. Looking at it will definately spur you on to improving your japanese. There's another good book called Japanese snow mountaineering with even more winter alpine type routes, but i couldn't find it on amazon. It's the same publisher/series as the below book and is number 58 in the series. Also look at the english language Hiking in Japan books, although they don't have technical routes they're still useful for general mtn info.
Am not familiar with good winter objectives in n honshu but there's plenty to do in the n alps, tateyama, tsurugi dake, yari, hodaka etc plus yatsu ga take (nearer tokyo).
I'm unable to share a rope with you as I'm in London. Try your local town/university/college climbing clubs. There are also a few brits based in japan who sometimes post on the ukclimbing forum who you could maybe partner up with.
Good luck and have fun, Japan is a great country for climbing if you have the time to get out. Spare cash and a car also help!!