Ian's answer has a lot of weight. You could buy all those books and read them all and know nothing about web development. What you really need to do is start with something that is not nearly as big as Stack Overflow. Start with your personal site. Read some web dev/css articles on a list apart. Learn about doctypes and why to use them. Add some css and change the colors around. Go over to quirksmode and peruse the site. Add some js. Follow some links on Crockfords site. You will probably stumble across his awesome video lectures, which you should watch. Then after that go back to all the js that you wrote and rewrite it. Then pick a server side language that you want to learn. Python is pretty easy, but it really doesn't matter what you pick. Then come back and integrate all those together in your site. At this point you will at least be getting started with web development and will have worked with several different technologies.
EDIT: I forgot to mention. READ BOOKS.
Many developers that I have worked with in the past have gotten through their career without really advancing after a certain point. I could be totally wrong, but I attribute it to not reading enough books and relying on using their same bad code over and over.
