"Holy Grail" Three Column Liquid Layout — Not Working

Hello all,

I’m a bit new to web design, but am beginning to grasp the basics. I’m trying to use bits and pieces of this layout to design a new layout for my organization’s site, here.

I’ve more or less kept the header and footer from my previous layout, and tried to implement the liquid three column layout for the content of my homepage.

But no matter what I use as my div classes, the columns appear at 1010px, (100% of my wrap). When I look at the css, it seems like the divs are picking up some elements (padding, overflow, and background color), but not widths.

Thank you in advance for any insight you can provide!