National Association of Photoshop Professionals (NAPP): A great resource for Photoshop news, tips, and solutions. Creators of Photoshop User and Layers magazines.
Dr. Russell Preston Brown: Fun, entertining, and highly educational. A must-see!!!
Kelby Training: Your resource for online training, books, DVDs, and other training materials for the Adbobe Creative Suite.
Adobe TV: Total Adobe! Everything you will need to get to know and master all the Adobe products. And it's free!
Digital Grin Photography Forum: A nice forum with some great contributors and threads relating to photography, Adobe Photoshop and Color Management.