For the legs, I use cotton bicycle tights in all weather except really cold
or wet. For those days, I switch to the gore-tex bicycle tights. They are
completely water proof, and are very comfortable for me. My wife says the
seams on these tights bug her, but I have not had a problem.
Skiing provides nice neck gaiters (gators?), facemasks, gloves, and thermax
long underwear for very cold weather. I don't have waterproof shoes yet,
but I'm working on them. (the bike stores do have waterproof shoe covers,
though)
Try any good motorcycle dealer (except Harley Davidson) for the off road
apparel. I get all of my bicycle clothes from Performance products. They
have a mail order catalog, as well as showrooms in a few places. If you do
some looking, you can get great quality stuff from other disciplines that
work perfectly for endurance riding. The best pair of riding gloves I ever
had were actually rock climbing golves.
Nick Warhol