w3schools for sure. They have an amazing set of tutorials that can get you up and running quickly. Other than that lots and lots of hands on experience. I think once you get the basics it's best to learn through trial and error. As you program you'll come up with questions, you'll be interested in learning because it will solve the problem at hand, and Google has all the answers :-), really there is a lot of help out there on the web. I'm working on some tutorials at Learn PHP in 24 Hours myself but I'm still a far cry from the quality and quantity at w3schools.com.
