i'd prolly check craigslist before ns... but you can go to the grocery store around you and pick up an autotrader, check ebay, car soup, local dealarships.
also, most of ns is under 20, and even then most 20 yr olds aren't looking to sell there cars.
oh and when you decide upon a car, make sure your mechanic takes a look at it. carfax might sound like a good idea, but it only shows the times the car was taken to a dealership to get work done.
I like my girls like Kool-Aid. Sweet and go down easy.