I have bought many independent games from http://www.kagi.com you need to register the game in their database and make sure you settle copyrights before you start selling it.
I found this on their about page: "Since 1994, Kagi has provided the place for thousands of software authors and distributors, content providers, and physical goods stores to sell online. Kagi's turnkey services allow sellers to quickly and easily deploy stores and maximize profits. The Kagi online store allows sellers to reach more customers while keeping expenses low." http://www.kagi.com/about/index.php