Have you looked at Redbubble? This a really switched on Australian outfit that are free to use. All you do is make your pics, upload and set the profit margins you want. They handle the orders and drop shipping and pay you the margin.
A recent addition to their features is your own "bubblesite". Check mine out at
http://glennb.redbubble.com/
Another feature is the Buyers Booth which features items bought through Redbubble from us artists. Nice for keeping an aye on the pulse although it is not comprehensive & relys on buyer's input.
Good luck with the search! Let us know what you decide to use.
GlennB
http://www.associatedcontent.com/use...39/glennb.html