Shopping cart question

Hello All, I'm looking to build a DB with items that are considered more of a catalog on one side of a website, and then provide those same items including the same images, descriptions etc. to a shopping cart. I don't want to re-invent all of the basic shopping cart functionality and I'm not sure I want to use something like OScommerce and inject the data into it at the same time as putting data into our database that we are writing. I was hoping someone out there has some suggestions, or even a cart module that would allow me to easily integrate into. Thanks! Jack