Replying to Europe in January

Ok so a few of us are going to have around 6 days in the alps to ski in early january (2-6th) and we are trying to figure out what we should hit.  First of all, how is accomodation at this time of year?  are we going to have to book stuff in advance or is it fine to just wing it?  I dont want to end up sleeping in the car, but i also dont want to book some place that ends up having shitty snow when there pow somewhere else.  Aside from that, basically we are driving down from frankfurt, but location doesnt matter too much since were used to epic road trips for skiing (last year road trip =4500km, 4 states and BC in the same time frame).

So basically, does anyone have recommendations for good resorts?  We like big mtn terrain, cliffs, easily hikeable stuff (were bringing transceivers, etc but no touring gear) as well as pretty much everything else the mtn has to offer.  Preferable places that arent too crowded and have a big variety.  Park is a bit of a consideration, but not crucial.  Ive heard about so many resorts and ive been to a few in the summer (laax, zermatt).  Ive only skiied hintertux in austria and it was june so i didnt really get a great idea. 

any ideas/suggestions/info would be much appreciated.

thanks