Chloe, there is a piece of software called Cartweaver which is what we use for our store. It is used by a lot of newbies and come in both ColdFusion and ASP flavors. It's found at
http://www.cartweaver.com/
Like Buffy mentions, Crystaltech is a host which also offer packages - recently they started offering free carts (ZenCart) which is based on PHP. The problem with choosing packages like that is that you pretty much tie yourself into one host, meaning that I don't know if ZenCart can be moved to another host after a while.
