Creating a site for selling computers

[Ferσή]

I'm creating a site for selling high end laptops using WordPress. However I can't find a plugin suitable for the level of customization I want. I'm not really sure what to do here, I don't code which is why I am using WordPress.
Any help or even a point in the right direction would be greatly appreciated.
Are there some free PHP scripts out there I can incorporate into WordPress somehow?
I'm looking for a menu similar to this:
http://www.pc-configurator.co.uk/pcconfig/new/cart.php?pcnew=2&freshconfig=0

[Cocaine]

You have to buy premium user to put custom stuff