I’m looking around, myself. Right now, Bonanza.com looks good. Sellers can upload from Amazon/eBay ads, Etsy and their own inventory files. What I don’t know is how profitable Bonanza is to the average seller.
Amazon just opened up their Amazon Handmade division. I don’t know a lot of details but it’s definitely worth a look. Something with Amazon’s trusted name on it should be a good thing, especially for new artisans.