I've colour coded each div so it's easy to see:
The header, colmask and footer divs are 100% wide and stacked vertically one after the other. Col1 is inside colmask.
The HTML in this layout validates as XHTML 1.0 strict.
That's right, you don't have to pay anything. Simply view the source of this page and save the HTML onto your computer. My only suggestion is to put the CSS into a separate file. If you are feeling generous however, link back to this page so other people can find and use this layout too.