If you administer the Windows Server 2003, you may find these sites useful:
support.microsoft.com/default.aspx?pr=kbinfo
www.microsoft.com/windowsserver2003/
Lots of useful stuff. Take the time to browse the site and become familiar with what's there.
www.microsoft.com/windowsserver2003/downloads/
Check this site out regularly for new add-ons and enhancements for the platform.
support.microsoft.com/default.aspx?scid=fh;EN-US;winsvr2003
Microsoft Product Support Services (PSS) site for Windows Server 2003 issues and fixes.
search.microsoft.com
microsoft.public.windows.server.general
This is the most active of the windows.server newsgroups on the msnews.microsoft.com news server.
www.winsupersite.com
The latest news about upcoming Windows platforms.
www.myitforum.com
The top site on managing Windows platforms, run by SMS guru Rod Trent.
www.win2000mag.net
News and content about the Windows platforms.