A good resource for would be managers is Manager Tools. I can't recommend this podcast highly enough.
I noted that one person said that you should let developers manage themselves. Unless the developer proves that they are self managing do not make this mistake! Most people are not good at managing themselves and need guidance and leadership which is what a manager should provide.
Don't weigh down your developers with useless time tracking tools. However, do put some good issue/bug tracking tools in place (phpBugTracker is one I prefer). There are also several good open source tools for tracking administrative changes that I would recommend looking into.
Remember to listen to your developers when they give you time and cost estimates. Track this type of information from project to project and try to improve upon it. You should be on the side of your developers because they have your back. The manager needs to stand between the developer and the client in order to act as a buffer between the two (I'm not saying that the two sides shouldn't interact, but when an issue comes up the manager should be there to handle it).
Encourage, pay for and compensate for training. It doesn't take a lot, it doesn't have to be $2K conferences, it could be a some study time, book and certification exam here and there with a small bonus for completing a certification. This includes management training for yourself!