your content area is 696 pixels wide, good enough to fit in the lowest common denominator of 800x600 resolution (still reporting at 20-25% useage) but it breaks (HSOD horizontal scrollbar of death) all the way up to 1024x768. Looks like you're designing for 1024x768 as your lowest common denominator as the width for the main layout table is set to 1024 but you've forgotten to accomodate the width of a scrollbar, and I just relaized you made this whole thing with Adobe Image Ready...
Use of a wysiwyg slicing tool like that stops the flood of info that was coming and causes me to ask, what exatly would you be interested in changing before I start to blow hard Some things that could or should be changed:
It's a very simple design that could be done without tables quite easily, and to much better effect.
Your main navigation is not complete and the remaining links are in the footer, probably below the fold on every page. A place where people would not normally expect to have to look for links to relevant pages.
Typography and color choices could be better, espeically the main header grahpic that just throbs, white and fully saturated red cause my head to hurt if I look at it too long, I'm serious!
Products pages should probably have thumbnailed images on the page that lists all three to keep them from taking up so much height and getting the up above the fold or therabouts. As it is is in 1024 it cuts off right after the first product, people will probably figure out that there's more below and scroll, but (it's been shown in older people esp) it may take them a sec to realize that, it's not a natural flowing process, which is what you should strive for when trying to sell something on a web page. And whene you reduce and image's size do it with photoshop or somesuch and not the height and width attributes in the img tag itself.
Anyway, great effort from a guy your age no doubt, but you'd be getting much better advice if you hadn't mentioned your age! If you're interested in any of the proposed changes and how to impolement them, post back, there's a bunch of people around that would be happy to help.