Being as big a fan as I am of WordPress — which powers this site and many others I’ve built — I couldn’t miss the opportunity to share a little guidance I recently offered a web designer friend who’s new to WordPress via e-mail:
The best place to start if you want to use WP as a blogging tool within an existing website (and on many other WP how-tos) is the relevant article in the WP Codex, which can be a little dry but is quite thorough.
An incredibly useful general info source is Smashing Magazine, which as you know is the no. 2 most popular and best-loved web design blog after A List Apart. Smashing is very WP-friendly and has a whole host of WP resources and tutorials here.
The best way to understand WP from the inside out is in two steps.
First, just do a fresh install somewhere on your own site, download a few themes from one of Smashing’s WordPress theme galleries or the official WP gallery, and start messing around, adding plugins, making sample posts and pages, sticking widgets in here or there. The WP 2.7+ backend is incredibly intuitive and requires virtually no explanation for basic functionality.
Once you want to get in under the hood and figure out what to do with the PHP and CSS files in the Appearance>Editor to make fully customized sites with real CMS functionality for clients, read through this great Themeshaper tutorial.
When you understand all the pieces of the puzzle that go into a typical theme, you’ll understand how to do just about anything you like.