Master dDo for Photoshop with this complete overview by Wiktor Ohman.
CGschool - Arch-Vis Training in 3ds Max, Photoshop and V-Ray
CGschool provides world-class architectural visualization training in 3ds Max, V-Ray and Photoshop.
Halo Speed Paint
Watch an impressive speed painting of Halo's Master Chief created in Photoshop with a Wacom Intuos4.