Got Artwork
Both a marketplace and a print-on-demand company, upload your artwork to Got Artwork to sell originals or prints. Got Artwork will print and ship prints for you. The process is very simple. Register for an account, and load your artwork. Indicate your markup for prints and whether or not the original is available for sale.
Costs:
Free basic account. Upgrades run $35 – 215 a year and include additional features such as custom domain, featured artist listing, and themable subdomains.