my blog

I have just learnt about the new Theme Developer Module for Drupal 6. This alone would be a good reason to upgrade if you are a themer. It is a development tool which allows inspection of the current page layout so you can understand what is influencing the presentation layer of the output. With the sometimes complex theming which occurs to a drupal page this is an invaluable tool.

There is an in depth screen cast and explanations on how the module works on the Drupal site. 

This is a great cheat sheet for Drupal Theme developers. It has some links at the bottom of the document to other references to.

I stumbled accross this guide to Drupal Theming today. You do have to register with the site and wait, but the document is good.