I need a shopping cart solution STAT

[Captain Insano]

Ok here's the deal... I am on my 3rd ecommercing design/hosting company and I have had it with their limitations and piss poor management of my business.

I need shopping cart development software or I need to develop one on my own.

What I would ideally like to do is design the entire front end of my website, add a few tags in the code and have it go into a shopping card that manages inventory. That shopping cart would be generated by some sort of software and the generated code would be uploaded to the webspace I own. I would probably have to buy some sort of digital certificate.

The website will be a build to order computer site, like CyberPower PC or in a small extent Dell.

What software might I be able to use to create my own cart? I really don't want to host it at a 3rd party. I want to get http://www.rackspace.com to do my hosting because they never EVER go down.

I need some real help on this. thanks.