You want URL's ... Get it ;-) (Score 1)

Very promising site (no software at this moment available) http://www.opensales.com/

It seems to me what MiniVend is the most advanced
OS solution available today.
http://www.minivend.com/iri/mvend.html

If you like Walnut Creek CD-ROM store then this stuff is for you
http://www.opencart.com/

Yet another Perl & MySQL marriage http://yams.screamdesign.com/

And at last, if you prefer to build systems by hand from simple blocks look at this page.
http://www.montana.com/ethan/shop.html