It's incredibly easy using Win32::OLE. You can use the application object named WScript.Shell.

  use Win32::OLE;

  my $wsh = new Win32::OLE 'WScript.Shell';

  my $desktop_path = $wsh->SpecialFolders('Desktop');
[download]

You can inquire about lots of other special folders using this interface:

• Favorites
• Fonts
• MyDocuments
• NetHood
• PrintHood
• Programs
• Recent
• SendTo
• StartMenu
• Startup
• Templates

I don't know what versions of Windows have the WScript.Shell interface. The only Perl dependency is the Win32::OLE module.