Craigslist is always a good place to start because there are no fees. User forums are the next best thing. After that, eBay will normally result in the item being sold if it's priced right.
One last recommendation: "I've done my best to accurately represent the item's condition but I am not an expert or fortune teller. This item is sold as-is."
You might take a small hit on the price by listing it "as-is" but you don't have to worry about the headaches of the after sale issues.