Can't help you with specifics, but I would recommend you look at nada.com and edmunds.com as additional resources. I may be wrong, but I thought carmax would give an online quote (subject to in-person inspection) -- but know you won't get from them what you'd get from a private party buyer, use their value as a "floor".
I'd also recommend cars.com and autotrader.com searches for similarly equipped models in your area to see what people are asking. Figure as a private party seller you won't get what a dealer is asking for theirs and also figure that every buyer will want to haggle the price a bit.
You also have a tradeoff to consider; price it lower for quick sale vs. get as much value you can even if it takes a while.