I have all three "JQuery Reference", "Learning JQuery" and "JQuery in Action"…<p>Of the three, "JQuery Reference" is the best — granted, you can access similar like reference material online, but I found it was nice to have in book form, with more examples, so you could leaf through when not gazing at a monitor…<p>"Learning JQuery" is decent, but dated, and many of the examples given use deprecated features. Also, some of the examples are quite contrived, and accomplish presentation tasks that I would never ever implement as JS. But my philosophy on JS is that it should enhance, and not be a replacement, so YMMV.<p>"JQuery in Action" — wish I would have foregone purchase of, not that it's bad, just that it seems to be packed with lots of verbiage and ends up being a poor man's ORA style "JQuery in a Nutshell".