It's unclear what the product is, or why anybody should buy. The layout is a little distracting, and navigation design could be improved.
Nothing hiring a designer and a copywriter couldn't fix.
In constrast, study
this RC Helicopter site. Clear layout. Clear copy. Clear proposition. You instantly know what the product is and what the objective is - a sale. Everything required for the site visitor to learn about the product and make the purchase decision is on the one page.
It's hard to tell you have anything for sale. And the way you've made it difficult to pay you is an obvious problem. You want a clear, simple, button "Purchase" or "Add to Cart"
Most people want to be up and running five minutes after signing for the package. You've got an uphill struggle with build-it-yourself. You've got to show 1) It's easy - for example show one of the kids built one 2) You can actually teach anyone, and testimonials show that beautifully. A key part of the product is that you are a good teacher anyone can learn from. If your reader can't even figure out what the site's about, they figure you aren't a clear communicator and so the instructions will end up being a door stop.
You could do well do study the site. It's the crib notes for the dozens of marketing, copy, and design problems which would fill up a dozen paragraphs to begin to explain. You have put numerous obstacles to purchase on the site. People do what's quick and simple -- grease the skids.