I've found a few interesting resources for Ruby on Rails stuff and I figure I'll link 'em up here.
First up, Railscasts.com; a collection of video screencasts on various small Rails tricks.
Next, a presentation from Dave Thomas at QCon about meta-programming in Ruby.
MetaProgramming - Extending Ruby for Fun and Profit
Rails 2.0 just came out, here's a post from DHH about some of the new features.
Rails 2.0: Preview Release
Also, if you don't own a Mac and therefore don't have that sexy Textmate editor, you might consider NetBeans 6.0. Netbeans used to be a joke of an IDE for Java but it's really come along nicely for Java and has really excelled in it's support for Ruby and Ruby on rails.
NetBeans: Ruby Developer's New Best Friend (Part 1)
NetBeans: Ruby Developer's New Best Friend (Part 2)