Well I thought I would try this css layout and at the same time go for xhtml compliant. Here it is -
http://www.teamcontractor.com/csslayout.html
It only uses css and it validates as xhtml 1.0 transitional - I also overrode the transitional and it tentatively validates at strict. Of course this is a very basic layout - but it works
btw - I did use a float style in a couple images.