For deleting all instances of an icon within c:\documents and settings\ <all folders> \desktop, I've used the attached vbscript. I didn't write it, and I actually don't quite understand it, but it works and that's all that matters to me. That particular example is to delete a shortcut called 'flow.url' from the quick launch and from the desktop of any profiles in c:\documents and settings.
To add a URL shortcut on the desktop, you could use something like this w/vbscript. If you want the AllUsers desktop instead of current user, just switch it in the code. If you use all user, you can run it via SMS 'whether or not user is logged in'. The script below would delete the Our Intranet.URL file before making the one you want.
Set sho = Wscript.CreateObject("Wscript.Shell")
Set fso = wscript.CreateObject("Scripting.FileSystemObject")
strUserProfile = sho.expandenvironmentstrings("%Userprofile%")
strAllUsersProfile = sho.expandenvironmentstrings("%AllUsersProfile%")
If fso.fileexists (struserprofile & "\Desktop\Our Intranet.URL") then
fso.deletefile(struserprofile & "\Desktop\Our Intranet.URL")
Set MyFile = fso.CreateTextFile(struserProfile & "\Desktop\Our Intranet.URL", True)