@author Kai Ruhl
For HTML, start with SelfHTML [de] to get a basic feeling for tags, contents and so on. If you have a header, sidebar and main content, you will probably want to use aside et al. instead of tables for layout; use with CSS for the final layout. Image tables should be done with figure.
Styling should be done exclusively with CSS [de], e.g. inspired by CSS Zen Garden. CSS layouts are a pain, particularly if you want a vanishing sidebar below a certain width, but with aside it is possible.