Search link (present in the right-hand side of the Start menu) is removed
when you install Windows Vista Service Pack 1. Also, the Search context
menu item is removed. There are other ways to launch search. For more
information, read this article.
Windows Vista desktop search Changes in Vista SP1:
http://support.microsoft.com/kb/941946
To restore the Start menu Search link, check the following links:
Search. context menu option removed in Vista Service Pack 1:
http://www.winhelponline.com/blog/search-context-menu-option-removed-in-vista-service-pack-1/
Restore the Start menu Search link in Vista Service Pack 1:
http://www.winhelponline.com/blog/restore-the-start-menu-search-link-in-vista-service-pack-1/