Here is what I use for my Digital Photography / Imaging students...

Digital Photography wiki

As well as some video-based items:

Check out the podcasts and online tutorials I created for my Digital
Tools class, which contains a complete college class in Photoshop,
Illustrator, InDesign and more. I am currently updating the lessons
from CS3 to CS4 for the fall semester, but it should still be a help.

Then click on the link for "Digital Tools for the Design Profession"