I’ve been using Shopify a lot recently as an easy to use hosted e-commerce solution. They have a handy theme editor called Vision that lets you create your own custom theme on your desktop and then upload it to your Shopify account. It is pretty easy to use if you are familiar with markup and CSS. They also have their own markup language for their application, called Liquid with a helpful wiki.
The only problem I find is that when I’m editing the .liquid files in Dreamweaver in Code View, the color coding on the markup isn’t there… it’s just all black text. Enter this handy Adobe Tech Note to the rescue: http://kb2.adobe.com/cps/164/tn_16410.html