Integrating a PHP cart/store with NS

We have an ambitious project and I'm looking for some good resources. In a nutshell, we would like to design a completely custom PHP driven web site and seamlessly integrate it with NS. The goal would be to still enter product data, inventory, etc., in NS, and have the PHP web site display the NS products. The PHP site would need to be able to pull not only product info from NS for display purposes, but also pull customer info, previous order history, etc..

I've read through some of the NS User Guide, specifically the SuiteTalkWebServicesPlatformGuide.pdf, and I understand the basics of how to do a soap call to retrieve records from NS, and how to insert new records. I also see that there is some sample PHP code. I haven't spent much time looking at the specifics of what records there are, and what records we would need to pull/push.