Colour Correction basics - an excellent tutorial video

Steve Hullfish Colour Correction

Replay: How often do people really take the time to explain the real basics? With stuff like colour correction, while you can and should rely on your eyes and a good, colour-calibrated monitoring system, you also need to make sure that your graded output is technically OK, or it might be rejected by your client

Almost as bad, you might find that you're not using getting the best out of your available media or equipment.

Here's a great video about colour correction featuring Steve Hullfish, via Editors Lounge, a forum organised by Alphadogs, a Burbank-based post facility. And while it's a few years old now, it's still very pertinent.