Options for selling really depend on what you have, and how quickly you need to sell.
I see a lot of collectors sell their best pieces in a hurry, which is about the worst way to do it... If you are thinking about selling, I'd put some low end to mid range points in a pretty frame and sell them on eBay. They may not be purchased by a serious collector, but someone will enjoy them and usually pay more than you'll get from us. (Most of us already have our own field grade stuff.)
Joshua