While jQuery is pretty awesome in what it can do, it also carries it’s own learning curve. If you’ve heard of jQuery, but haven’t had time to play around with it or kick the tires, you might be interested in this series of videos about jQuery from AJAX Experience, which includes the Intro to jQuery by its creator, John Resig, below:
Bummer...looks like the videos have been pulled, and I cannot find another source for them. That's a shame, because they were quite good. Well, there's still the tutorials and documentation on the jQuery site itself.