The site is looking better everyday!
As mentioned by a few people, it would be better if the page was centred. This shouldn't be a problem though.
You can set the width of your tables, ensuring that you never go bigger than the screen resolution. There are two ways you can do this.
1) You can set the with in Pixels so that your table will never go wider than the screen. So the Table Width can be set to 800 and it will never go wider than 800. But this means that someone with a 1024 width screen will see lots of white background.
2) Set the width as a percentage rather than a set width in Pixels, and you can get around the white background problem. So, set the width to 95% and on an 800x600 screen, the table will only go to 760 pixels (20px of white per side of the table). On a 1024 screen the table will be 972.8px.
Both ways have their downfalls. The first shows too much white on your background, but with your current page, I don't think the white goes down too well at all (white is very corporate and modern and doesn't suit your site IMO).
The second one shows a lot less white, but can make the page look stretched on a larger screen if all your layouts are wrong.
I would suggest you use method 2 and set a percentage your happy with. This should cover most of the bases and resolutions.