I was trying to make a three column layout using absolute positioning, so that I could keep the content at the very beginning of the code and put all my other stuff (nav bar, ads, etc.) at the bottom of the code.
I don't know what you mean with a fluid content section, but from what i can see, is that you can add
to the content section in your css. this will move the content section away from the right box, but it will be fixed at that position.
Another thing about absolute positioning that took me a while to figure out, is that if you have something that needs to be abs positioned inside a box, you should make the Containing Box
-> position:relative <-
The reason for this: You can control the abs positioned element from within the box. Otherwise you'll have to control it from the browser window coordinates, which can be quite painfull... Trust me, I have had much trouble with this...