Alright, I'm brand new to the forums here and was wondering, how do websites such as the ones listed below work their shopping carts out?

I noticed with them, that they are using ColdFusion so I'm new to the ColdFusion world but that is what I am ultimately trying to become familiar with.

I would like to know how these car sites are designed that make certain parts availible for certain years, makes, engine sizes, etc.

How could I create a site under the same principal. You pick a year, then it gives you manufacturer and then model, all dependent on your previous entry.

Then when it comes time to check out, what type of shopping cart application would I need to use to be able to integrate all of that data?

Thanks and I hope some of this will make sense to someone.