" How do I get 'User Manager' and 'Server Manager'? "
Since I do not need to buy an NT4 Server, how do I get the 'User Manager for Domains' and the 'Server Manager'?
Microsoft distributes a version of these tools called Nexus.exe for installation on Windows 9x/Me systems. The tools set includes:
Download the archived file at ftp://ftp.microsoft.com/Softlib/MSLFILES/NEXUS.EXE.
The Windows NT 4.0 version of the 'User Manager for Domains' and 'Server Manager' are available from Microsoft via ftp  .