I think this is a great read, even for non-designers out there.
Color Theory for Designers, Part 1: The Meaning of Color
Color in design is very subjective. What evokes one reaction in one person may evoke a very different reaction in somone else. Sometimes this is due to personal preference, and other times due to cultural background.
Color Theory For Designers, Part 2: Understanding Concepts And Terminology
If you’re going to use color effectively in your designs, you’ll need to know some color concepts and color theory terminology. A thorough working knowledge of concepts like chroma, value and saturation is key to creating your own awesome color schemes.
Color Theory for Designer, Part 3: Creating Your Own Color Palettes
Here we’ll be talking about methods for creating your own color schemes, from scratch. We’ll cover the traditional color scheme patterns (monochrome, analogous, complementary, etc.) as well as how to create custom schemes that aren’t based strictly on any one pattern.