MJ, what you are doing is a little more manual than what I am looking for but thanks for the posts, you've shown me how I can hack a few things if it comes to that.

Sticking to the Amazon example, what I would want is to use a web service to grab products from Amazon and update my product catalog with them. Then users would come to my store and purchase them (on my store, no redirection). Then I would notify Amazon of the sale so they could drop ship to the customer.