I Vote For Art is a great website published in Melbourne by Ben Rowe, selling a range of affordable artwork - in a similar vein to Thumbtack Press that I have written about before.
There are over 30 artists represented on the site from Australia and around the world, showcasing mostly modern and contemporary artworks - many with a commercial/graphic design edge. There are lots of great illustrative pieces from up-and-coming artists including Aussies Skaffs, Yiying Lu (of the Twitter Fail Whale fame), and Sandra Krumins.
Purchasing a print is an easy process using Paypal (in US dollars) and I Vote For Art will ship to your door. And for artists, this is another great way to get your work 'out there', especially as the voting system on the site means that the most popular pieces are highlighted on the I Vote For Art homepage. I'm definitely for any website that promotes artists and makes it easier to both buy and sell art, so make sure you add this virtual gallery to your bookmark list.
Images: top - I Vote For Art, middle - Fail Whale by Yiying Lu, bottom - Owl Tree by Sandra Krumins