This week's book giveaway is in the Other Open Source APIs forum. We're giving away four copies of Storm Applied and have Sean Allen, Peter Pathirana & Matthew Jankowski on-line! See this thread for details.
The first think you'll need to decide is whether you want to learn Struts 1 or Struts 2, because they're quite different. Unless you're learning Struts to support existing applications, I'd recommend Struts 2.
For Struts 1 tutorials, there are some good suggestions in the FAQ. For Struts 2 tutorials, I'd start at this URL: