Agreed. You don't need Dreamweaver. Look at aptana instead.

The free community edition is more than enough. It's based on the extremely popular eclipse editor for Java.

In terms of a methodology, I'm not exactly sure what you mean.

Be sure you know plain XHTML by hand first (Aptana will help you write the code, but you have to understand the code.) Don't rely on a visual WYSIWYG tool like Dreamweaver, because when you're writing PHP code, your own code creates the XHTML. You've got to know how to write it if you're going to write a program to write it.

Learn standards-compliant design: CSS for layout – no tables. Dreamweaver teaches bad habits you'll have to unlearn eventually.

Once you can create a web page, start working on JavaScript (it's cool again, thanks to AJAX) and PHP to add interactivity and permanence to your sites,

For commercial work, you'll eventually need database work, and MySQL is hard to beat.