I'm mostly a content editor who has front-end development (a la Dreamweaver, hand coding HTML, CSS) experience looking to delve into the world of Drupal theming.
Can anyone suggest a training book or video series that walks you through designing a site from the ground up? I'm currently viewing a video series at drupalize.me but I think I need something a little more in depth.
Appreciate any suggestions.
Wow, that's a difficult one. Drupal having so many themes and modules you can plugin that change the nature of how you would go about themeing. For our staff I have them set up a test site then create a subtheme folder and starting playing with the CSS file directly while using the web developer and firebug firefox plugins. Once I showed them the plugins they started understanding how Drupal was putting things together. - We also standardized on a common set of plugins for our sites, which also made it easier.
I recommend "The Definitive Guide to Drupal 7" from Apress, it is a serious chunk of paper. There are two solid chapters on themeing and some other good stuff with drush and version control that you may find useful as you start developing. I also agree that getting in and playing is the best way. There is also an IRC channel #drupal-themeing