AutoTrader is a reputable website that provides listings of used vehicles for sale both by dealer and by private party. Users can search within their zip code or between 10 and 500 miles away from their current location.
Users can customize their search on AutoTrader in almost all fields. Parameters can be specified for features such as body style, model year, fuel economy and transmission. Craigslist is another good tool to search for used vehicles. Users can select an area from Craigslist's front page and search for used vehicles within that area. Craigslist does not offer the array of customization options that AutoTrader does, but it does offer a wide selection of used vehicles both from dealers and private sellers.