@pyroMay 28.2003 — #When 'graphics' and 'free' are used in the same sentence, I think of [URL=http://www.gimp.org/]GIMP[/URL]. As far as shopping carts go, you will have to use some server side language, or pick up a pre-built one...
@Compguy_PeteMay 28.2003 — #are you looking to post links about the graphics or just for your own learning? it would be helpful to know which programs your interested in examples Photoshop, fireworks, PSP or MS paint.
I totally stand behind Pyro's suggestion of agoracart, it has a lot of features. the only downside is the templates for the cart could be a bit easier to deal with and take some time for most to use.
Other than that you can do either online or offline CC processing and support for all the popular Payment gateways. Authorize.net is my personal favorite to use with agoracart.