http://blogs.msdn.com/sharepoint/archive/tags/Search/default.aspx - search related from Microsoft’s Sharepoint Product Team – also includes ‘How We Did It’ links for other customers

http://technet.microsoft.com/en-us/library/bb735129.aspx - written by Microsoft IT on how Microsoft has used search  internally

http://www.microsoft.com/sharepoint/capabilities/es/overview.mspx - Enterprise Search whitepapers and webcasts

http://www.microsoft.com/enterprisesearch/ - plethora of resources on Enterprise Search including analyst write-ups.

For governance I would recommend looking at the section on Governance at http://sharepoint.microsoft.com/gearup/Pages/Governance.aspx in addition to the information available from the Microsoft Governance Team at  http://blogs.msdn.com/nickmac/archive/2008/11/06/sharepoint-guidance-from-patterns-practices-team.aspx

Thanks to Kirsty Cook for providing these!