Computer Power Users [CPU] forums have a buy/sell forum. I think you have to be a subscriber to one of their mags - CPU, Smart Computing, and there are some others - to join the forums. They do have a cheaper online subscription that gives you access to all articles and forums without receiving the print magazine. I haven't read the rules for the buy/sell forum, but you could check it out.
It is a good idea to "recycle" software and hardware. I sure bought a lot of software I never used - outdated now. Software is just so tricky because of that ability to make copies.