Adjusting each individual channel is basically using Auto Levels, which you can use more effectively in the Levels dialogue box with the Options button. Set it to Snap Neutral Midtones and Find Dark and Light Colors, set the clipping to around .02% for starters, and save that as the default. That will give a good starting point for neutralizing color casts and getting the full tonal range without clipping any channel. (And anyone with more experience with it, please jump in.)
The best advice I can give, though, is to get Blatner/Fraser's "Real World CS" or Eismann's "Restoration and Retouching," both of which have good, clear segments on using Levels and correcting color and why it all works as it does.
By the way, I gotta speak up for Jonathan. He answered my early questions when few others would, and his first reply to you wasn't meant to be offensive, just an aside from a pro.
Picture someone in a movie asking Clint Eastwood or Anthony Hopkins a question about levels, and the old photographer says, "That would be because altering the value of one color channel vs another is how you get different colors in a digital image. Your question is sort of like asking why fire is hot."
In the movie, the person would go, "Oh..." and go off and think about it 'cause he'd know he was just clued into something very basic that he had to learn.
But hovis, you shot back with "Learn some manners, if that's the best reply you can come up with don't bother."
We all react badly to misperceived slights, and it's one of the dangers of forums, but since you asked for help, and just joined the site this month, I'd say the manners should start with you.
Good luck with it all, and see you on the boards.