I don't normally like to recommend one commercial solution over another. Mainly because I don't want to be held responsible for the vagaries and consistencies of a product or service and also because there are almost always pros and cons between the different product and service providers.
However Artisteer is a bit different. They have been around for years, the product does exactly what it says it does and there isn't really any alternative - the product is unique.
Artisteer is like having a CSS guru inside your PC. You can click on and choose from the whole site layout options to tiny button and tab configurations. You can even add Flash and pretty nifty scrolling banners and so on. We will do the latter in a minute.
Tip
Excessive use of these features raises the possibility of JavaScript conflicts with VirtueMart. Add a feature at a time and test regularly.
It is certainly true that you probably won't end up with a design...