University of California
Knight Digital Media Center: Photoshop
Learn Photoshop editing in this tutorial designed by graduate students from Cal State Berkeley.
Other
Photo Funia: Effects
If you're looking for a quick and professional picture effects online service, then PhotoFunia is the cite you've been looking for. This collection includes over 600 effects.
Goodwill
Gcf Global: Image Editing 101
In this tutorial, get tips on editing images so your photos look their best.
PBS
Pbs Learning Media: Tricks of the Trade
This document shows you how to capture and edit still images from a video segment, using either a PC or a Macintosh computer.