There is a lot to painting a car and having a quality outcome.
It would be best to take it in steps and try not to squeeze all the information required into one post. You can lay down the best paint job ever, but if its over poor prep work, its going to look like shit.
Auto Body Toolmart
is a great place for products. You're going to have a tough time finding jobber that can beat their prices.
As far as information, you might want to head over to Auto Body 101
and read as much as you can over there.
You need to focus on having a proper prep job, then focus on paintwork. You can post up some photos of what kind of repairs your about to head into and we can give you some advice based on those.
You need to becareful spraying metallics or heavy pearl colors, if you finish sand in 320 like stated above, the metallics/pearls will lay in the sand scratches and look awful. Everything should be finished in at least 600 prior to paintwork IMO.
But something that hasn't been mentioned yet, respirator. Don't use some POS dust mask that you see guys hanging drywall use. Go spend the money on a proper respirator. These are not friendly products you'll be using. Treat them with respect.