AutoCAD — HELP!!

The AutoCAD support tech for my company has just turned in his resignation, and I’m expecting to have to support the AutoCAD users now. Well, the only thing I know about ACAD is what the name is. Where can I get some top quality info in a hurry??
Network: Novell 4.x svrs, WinNT4 wstns (soon upgrading to 2000), FDDI nwk.