Wet and cold weather photography is as much about what you wear as it is about the camera gear! If you feel warm and dry, you will stay out there longer and get the shots that others miss. Fortunately for me, we have some GREAT thrift stores in Tahoe. Not the cheapest, but they have fantastic gear for far less than REI.
Boots- get ones with good tread, Gore-Tex waterproofing, something good for puddles and snow crossing. If you might hit icy terrain, carry yaktrax or other microspikes.
Pants- Get some ski pants at the thrift store, bigenough to pull on over your regular pants. This will make a HUGE difference!
Jacket/ sweater- I layer these, so I can pull on a shell when the rain/ snow hits, then pull it off when the sun comes out.
Hat- I weat hats, rain or shine. My usual hats are wool felt, so they keep me a little warm in winter, but smell like a wet dog if it rains! I wear beanies if it is really cold or windy.
Gloves- Remember that yu need to keep working your camera, so fingerless is good if it is not too cold. Or get the kind where you can slip a finger through. The main thing is, you don't want to keep putting them off and on.
Umbrella- These are great because they protect you and your camera both- but the wind is a problem. And often they make you wish you had three hands!
In Conclusion- the wrong clothes make you want to stay indoors. The right clothes function as an important component of your photo kit!