IBM developerWorks has published two tutorials on how to use ECS with PHP 5:
This is the first of a two-part tutorial that constructs an Amazon storefront using PHP and the Amazon E-Commerce Service (ECS). The storefront constructed will allow shoppers to view items displayed in lists or search for specific items in the store.
This is Part 2 of a two-part tutorial that constructs an Amazon storefront using PHP and the Amazon E-commerce Service (ECS). This tutorial shows how to create a shopping cart, a “browse for similar items” feature, a specialty theme shop, and a collectibles shop.