Try this out:
http://www.cubecart.com/
I'm not sure of their quality, but this is one of the many selections you can look at.
http://www.novainfo.com/products/software.asp Viaklix is also a very good choice if you already had a shopping cart set up..
Or maybe even Yahooshore?
Hopefully someone better at this than I am can chine in and lend some more help or suggestions.