Stop trading your car to the dealership!!
I'm finding it nearly impossible to find any decent private sales, and it's because people insist on letting dealerships rip everyone off. When you filter autotrader for private sales, you eliminate 90% of the options. Trade-ins are the worst, because they get you coming and going. Before you trade your car in for $8000, sell it to me for $10,000 instead. That way I don't have to buy it from a dealership for $12,000.
Check out caRpetbomBer's picks in this thread.