Markup and Style
W3 School has good free tutorials, with certification available for a fee. For starters, I recommend the ones on HTML, XHTML and CSS.
CSS Zen Garden shows the why of CSS. Each version of the webpage is the same HTML file, but with different CSS files. Select a design from the right menu column. It’s an amazing demonstration of seperation of content and form.
Read the Web Style Guide for basic design principles. Poorly presented content is absorbed poorly.
