http://pudget.net/macperl is the home of Chris Nandor's Perl modules. Nandor is one of the most active developers of MacPerl modules (and co-author of the book cited below).
http://www.activestate.com/support/mailing_lists.htmhosts the Perl-Win32-Admin and Perl-Win32-Users mailing lists. Both lists and their archives are invaluable resources for Win32 programmers.
http://www.microsoft.com/management is the home for all of Microsoft's management technologies, including WMI.
http://www.sysinternals.com is home of the nthandle program (called just Handle on that site) and many other valuable NT/2000 utilities. It has a sister site, http://www.winternals.com, which sells excellent commercial utilities.
MacPerl:Power and Ease, by Vicki Brown and Chris Nandor (Prime Time Freeware, 1998) is the best book for information on MacPerl modules. The publisher also has a web site at http://www.macperl.com that is very useful.
http://www.dmtf.org is the home of the Distributed Management Task Force and a good source for WBEM information.
http://www.mspress.com are the publishers of the Microsoft NT Resource kit. They also offer a subscription services that provides access to the latest RK utilities.