From the WotC site– a few recent articles that are interesting or adaptable.
Secrets of Xendrik maps Lots of maps you can use for different ideas.
Templates and character types The concluding article in the series, walks you step by step through adding a template.
Kibbitzing on monster variation— advantages and disadvantages of variation in foes; why fighting one thing gets boring, but a return to a foe can show what you’ve learned.
Dragons of Faerun Table of Contents (for Dad, since he expressed an interest)
Adding a few more:
Iron Kingdoms Firearms (pdf) Black Powder rules for D20.
Pathguy’s Character Generator is thorough– one long page that assembles your character w/ JavaScript. Uses the Completes and other advanced sources.