Management Tools for Computer Labs?

dorko72 asks: "I have been put in charge of setting up a small computer lab (30 workstations) for a local community. The benefactor is providing the hardware (dell workstations and one server) as well as the operating system for these systems (Windows XP Professional and Windows 2000 Advanced Server) All the equipment is used, but not too old. I would like to find out what some of you guys use to monitor and manage the lab usage (ie provide realtime stats of which station is in use, etc). I would plan to set these machines in a Windows domain using Win2k Advanced Server as the controller via Active Directory. There must be some way to access AD and find out who is logged in to what machine in the domain. Any suggestions or ideas would be much appreciated."