Color Theory
Adobe Kuler is a great resource for creating and finding custom color schemes for projects.
Color Method– test your color matching abilities.
Logos
Typography
I Love Typography is a great typography blog by John Boardley.
Elements and Principles
The Lost Principles of Design by Chad Engle
Composition and Design by Marvin Bartel
Method of Action-is a collection of tools games and articles to help you learn design.
Printing
Free Stock Photos
Wikipedia: Public Domain Images Stockvault.net Pixabay Flickr Commons Morgue File Everystockphoto
Photoshop Tutorials
Adobe TV Photoshop Cafe Photoshop Creative Planet Photoshop Abduzeedo Layers Magazine