Wheres a good place to buy a used car in nyc?

So im a college student and i really need a car so im loooking to spend around 4,000 for like a mitsubishi eclipse or lancer, somehing small and nice to begin with. I was wondering any good places around nyc or westchester or nj that has a good selecion of cars or somewhere to start? I've tried craigslist but wanna know if any place else, or maybe financing options as well. I wanted to also know the process of getting a car as like driving off the lot.