Where to trade games?
Try using the words "Game Trader" or something similar in an
online search. My work firewall blocks any sites with the word
"game" in them, so I can't give you the exact urls, but "Game
Trading Zone" and "The Game Trader" both look like the type of site
you are looking for. Whatever type of game it is, board game or
video games, there are also sites online that buy and sell used
games, if you can't find the trades that you are looking for.