Stopped by the Macromedia site today (btw – they redesigned for the launch of their MX 4000 versions of their products) and found that they have a number of pretty cool tutorials for PHP, CSS (here specifically for dreamweaver) just to name a few. (look on the side in "topic centers")
Here's one for how to create a persistent shopping cart
Here's a bunch on CSS in Dreamweaver … including one on creating tableless layouts using CSS in Dreamweaver