3 Columns Problem

This is my first XHTML/CSS layout...

The layout is using 3 vertical sections. A left section, middle section and right section..

Basically, the middle section is going under the left section and the right section under that. I have floated the left section left and right section right. I also tried clear but could not get that to work either

Here's what I mean: Link

Help appreciated

Also worth mentioning...I know there are other errors :P if you know how to fix those too that's great.