Other than eBay, my only experiences have been a couple of silent auctions for silly stuff, and for a couple of years, several visits to a nearby rural-ish auction house. That was a great deal of fun for browsing various and sundry things, occasionally bidding on something, watching the auctioneers, and soaking up the general atmosphere and camaraderie.
Then they decided they could do better as an online auction house, which I thought for their general range of goods and activity, was inappropriate. It destroyed the regional feel and the whole social "real life" experience of it all. (This was nothing like the kind of venue or level that BK is talking about.)
I've never sold anything at auction, only bought a few things, but I think auctions are fascinating and an exciting experience. If you haven't tried one, even as a spectator out for some spectating fun, do it sometime.