The idea to create an eShop on my website was floating for a long time in my silly head. Actually, I've even started this endeavour, but has not completed . And here is what I discovered in deep ocean called Internet - WebAssist eCart. It integrates with Macromedia Dreamweaver and PayPal Pro (but not the only one). So you process your transactions and credit cards seamlessly. There are a lot more to it:

• Powerful, flexible shopping cart control
  
  • Custom shopping cart columns
  • Create shopping carts your way
  • User-definable calculations
  • International support
• Unparalleled checkout options
  
  • Leading gateway providers supported (AuthorizeNet, LinkPoint, PayFlow, PayPal Website Payments Standard, 2CheckOut, WebAssist Payment Gateway, and WorldPay)
  • Personalized checkout configurations
  • Real-time FedEx and UPS shipping
  • Same site checkout options
  • Complete form creation
• Expertly-designed shopping cart displays
  
  • Professionally crafted designs
  • Different shopping cart types available (Updateable cart, Read-only cart, QuickCart, Email-friendly Cart)
  • Show and calculate discounts and charges
• All the tutorials and examples you need
  
  • Premium support incidents included
  • Getting started guide and contextual help
  • Complete sample store
  • Administrative example
• Application Server Models
  
  • Coldfusion 5.x and later
  • ASP JavaScript
  • ASP VBScript
  • PHP 4.2 +
• Databases
  
  • Microsoft Access
  • Microsoft SQL Server
  • Oracle
  • MySQL 4 and MySQL 5

And it is considerably cheap - $199.
Check out their website for more information!