Can't help you (no longer ski tahoe) but if you are lucky your university might have a ski lodge there (surprisingly many do! donating a tahoe house is a popular and profitable gift item). Some have been opened up to the public (becoming like a B&B). A very good one at Alpine Meadows is http://www.stanfordalumni.org/learni...alet/home.html
which used to be exclusively for alumni but is now public. If you cannot find a season rental something like that might be a better alternative than motels.