I have skied most of the major resorts world-wide and have never seen a ski clothing rental store. I guess it's assumed that if you can afford to ski, you can afford clothing.
Having said that, you don't need to buy a US$1000 ski outfit. Any jacket that will keep you warm down to about -10C will be fine. If it's colder than that, you won't want to ski anyway, no matter what you're wearing.
The same goes for pants... just wear long underwear underneath.
One thing to keep in mind is that you'll want a jacket and pants that snow won't stick to. Otherwise, you'll get wet and mierable very quickly.
One solution is to wear a cheap nylon layer over top of your jacket and pants, if they're not water/snow repellant. Something like a light rain shell for the top and nylon (or similar) jogging pants over your regular pants.
You won't be making a fashion statement, but if you're a beginner that won't matter anyway.
The important thing is that you'll be warm and the snow will fall off of you if you fall.