In reply to Duncan Bourne:
East face of Tryfan and much of the Llanberis pass are not really places for beginners at the best of times, and certainly not through the winter.
Chrissy - a few questions before we can give really good advice:
Just how recently have you started? What climbing have you done?
Can you lead on Trad gear or are you looking for sport routes?
Where in North Wales are you?
There are lots of smaller 'single pitch' crags that are probably better to start on - you can put up top ropes if you're not confident at placing gear, or move on to leading either sport or Trad - just depends on what you're looking for. And if you want to get started at this time of year choosing a crag that's sheltered and dry will be important.