There are many other online fixed price listings sites.
Etsy and Amazon are the best known.
Amazon doesn't cover the same variety as eBay concentrating on New items. If they don't already sell it, it can be difficult to list it. Shipping costs are strictly controlled.
Etsy specializes in handmade items with some vintage. Their customer demographic skews strongly to women.
Ruby Lane specializes in high end vintage and antiques. Beautiful site, but they do have listing fees.
Bonanza is easy to use (you can transfer your eBay listings with one click) and free, but I admit that sales are very poor, I have had over 20,000 listings (books and stamps mostly) at a time there with sales in the tens. As in less than a dozen sales annually while the same material on eBay is selling briskly and daily.
The only online auction site I know of is Delcampe Auctions, based in Italy. They specialize in philately, but do have some outreach to other collectibles. The site is in English.
I have or do list on all these sites. YMMD.
