It is a very busy looking site. When I pulled up the site, my first thought was "Template, Too Dark, and Busy." There is a lot of product that is well organized and that is a plus. I would make a completely new design on a dev server. Go for a design that makes the co. look unique. This post comes to mind.. (Look for the DecentBanners post) That site uses nice custom, vector graphics to present itself as a custom unique co. Learn to use white space... let the visitors eye read the message you are trying to deliver. Even on Decent Banners.. there are 3 check marks that read Unique...Quick...Drive... I would pop those out with additional outline. Make your actions and site go BAM! It should be quick to read... in 3 seconds. For example... Accessory Genie has 3 or 4 different colors of blue. The design falls apart right from the start, and the gold buttons on the top left look out of place. The javascript flyovers are annoying too, dump those.

Sorry to bash.. re-design is a tough choice. Especially if you're using a free shopping cart system. I would put energy into 3 areas... finding a better shopping cart system that will allow a developer (not designer) to tweak the design as needed. Find a designer that is very good in vector based designs. And make sure somebody knows how to export and successfully re-import all your data with the correct DB mapping. Best of Luck!