You want to take the engine out and sell it separately? Or you want to just re-sell the whole car? If you just want to sell the car then look up the value, it's not hard.
Go here:
New Car Prices | Used Car Values - Official Kelley Blue Book Site
If you're talking about pulling the engine and selling it separately...well, honestly, I think that's a dumb idea. What are you going to do with the chassis afterwards? You'll have a useless, motor-less car sitting around. I'd just sell the whole thing.
Did you get a really good deal on this car or what? I don't understand why you'd buy it just to turn around and sell it again...