WordPress Theme blank has no layout but every template is full of html comments to explain the php stuff if you know a bit of css and html but php is a bit of blur with you ;-)
Article and download: WordPress Theme Blank.
There is also a sample style.css full of necessary classes you need to style a WP Theme.
First release was May 2006 and now there are more than 45thousand downloads and 5updates in all this years.
Enjoy!
License:GPL ;)
kindly regards
Monika