I started selling on GraphicRiver.net. The site is a spinoff of FlashDen.net. Selling on Graphic River is very easy. You first have to read a set of instructions for posting graphics and trademarks, copyright infringement, etc. Then you take a test that is basically an overview of what you just read. Once you pass the test, you’re ready to sell.
You can upload a variety of graphics into different categories. You don’t get to set the price of the graphics you sell and graphic river takes a cut of the profits, but at least you can make money online, which is ideal.
Graphic River will review all of the materials that you upload and they actually turned down a few of the pieces that I sent them. It takes a while to figure out what they are looking for but for the most part, they are looking for original, trendy, graphic work.
If you’ve got the time and are willing to commit to their rules, it might be worth it to start submitting artwork to them.