Posting after midnight and then at 2 AM is bound not to receive an answer until later during the day... give people some time to answer before bumping your own thread.
The Today screen plugin for Windows Live Search is part of Windows Live, not to be confused with Live Search, which is what you are downloading.
You can find it here:
http://www.microsoft.com/windowsmobi...oad-en-us.mspx
However, this version does not include Windows Live Messenger.