Most Wal Marts are free overnight parking so if there's one near the hills you're good. THe downside is some is only for RV's and bigger vehicles. I've been kicked out of a few for camping in cars. It's not hard to find a place to park though, just find some back area around a building. But first things first is find out if your mountain allows it. Most resorts where I've been are down with it you just have to be respectful.
I remember reading Alex Martini say somewhere his tips on staying warm through the night and stuff. He says to get the AC going until you're really nice and toasty (car running, can't risk the battery) then shut it off and hit the hay. You'll wake up from being cold more than halfway through the night so at this time turn your car on and let it run with the AC and fall asleep again. It's just idling that's the problem for the outside so it will vary on where to park using this method. But it works wonders, hardly uses any gas either. As for recreation bring a laptop if you have one, some movies pre-loaded and all that jazz.
To get really into the rhythm of car camping it's all trial and error, your first few days will be a learning experience but once you've got the gist of what you want and your own methods it becomes so much fun. Super comfy once you get the perfect set-up and nothing beats being first person at the hill.
