how to learn php

hello i have been trying to learn php. what is the best approach to learning php for someone who has no programming experience? i am very familiar with html, xhtml, and css. i'm not an idiot when it comes to using computers. i have bought several books and have subscribed to a couple of the php mailing lists, but i feel that i could be doing more to learn php. what approach (and steps) did you take in learning this really cool scripting language? should i look into taking classes or stick with an autodidact approach? any advice and/or opinions would be greatly appreciated. thanks.