On one of my other blog posts, Steve (who clearly shares my love of RegEx.... and is smarter than me in that department) was telling me about Possessive quantifies in Regular Expressions. I had never heard of this and so, I tried to look it up on Google. What I found was a little confusing and I am not sure I understand it that well. But, in my searches I came across a Regular Expression Tutorial over on Sun.com. I had never seen it before and clicked through it. Upon a brief review, it seems to be one of the nicest RegEx tutorials that I have ever seen.
Take a look at it: Lesson: Regular Expressions
Usually, when I have questions about Regular Expressions, I turn to http://www.regular-expressions.info. This is also an amazing sight, and perhaps has more information and a host of excellent examples. But, it might be a bit too much for people who have never dealt with regular expressions before. The tutorial on Sun.com might be a bit easier to digest for beginners.