I sell on eBay. That's where the buyers are. At least for a lot of the things I sell. Just started selling on Amazon but that's for new stuff with a UPC code.
I checked out yardsellr. Looks cool. Not yet ready though. I'm looking to make more passive income than anything. Consulting, eBay training, etc.
I do have my own auction site at
http://www.vintageonlyauctions.com. I have bundle lots there. Something I plan to grow at a later time. Also a solution for vintage sellers that have their own traffic yet need an auction site other than feebay.