You could try to sell it here, on the for sale section of the forum. Your local Craigslist might be a good bet. Or eBay. If you try to sell it online you are going to have to give more information so people can judge whether the bike will fit them. You should at least measure the distance from the ground to the top of the top tube so people can know if they can stand over the top tube.
Your best bet may be local as the bike would be a pain to ship and may not be worth the money to justify shipping.
Trek Madone 4.7 WSD
Cannondale Quick4
1969 Schwinn Collegiate, original owner
Terry Classic
Richard Feynman: “The first principle is that you must not fool yourself and you are the easiest person to fool.”