JRK -- i'd recommend taking your car to carmax. my bro works in the car sales biz and he always has me take my car to carmax for an appraisal. they usually offer more than dealerships because dealerships like to say -- "oh yes we'll give you $1000 more on your trade in than carmax". and then they add $1000 more to your purchase price of your new car.
plus you can just sell the car at carmax and not buy another car. i've sold 4 cars at carmax. yes i go through cars like i go through underwear. once a year.