CHECKOUT BY AMAZON INLINE SHOPPING CART

I want my cart to be build for my wordpress website. Content is already on site and I am ready to go including fotos and info, and product prices ( however i want to change prices easily. Looking for good work and to be done efficiently for a fair price. I have cart66 and WP Ecommerce downloaded plug-ins installed already. I am thinking these are efficient unless since you know about Amazon and maybe there is a better source free of monthly fees. Any ideas regarding this would be appreciated. Thank You for your interest, Randal