PowerGui
I found a nice little tool that helps you get to grips with Windows PowerShell. Its an easy to use GUI that includes all of the powershell commands you will need for AD and Exchange. I've been using it mostly for reporting where its easy to format the results and filter just the information that you want. It also shows the scripts that its creating in the background to give you a better understanding of whats going on.
Its a free tool and can be downloaded from
http://www.powergui.org/index.jspa