Upgrading Active Directory Domains to Windows Server 2008 and Windows Server 2008 R2 AD DS Domains

http://technet.microsoft.com/en-us/library/cc731728%28WS.10%29.aspx

http://technet.microsoft.com/en-us/library/dd464018%28WS.10%29.aspx

http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=fa629de2-f4dd-47ac-8d80-3db46b2877a2

http://technet.microsoft.com/en-us/library/ee522994%28WS.10%29.aspx

Upgrading Active Directory Domains to Windows Server 2008 and Windows Server 2008 R2 AD DS Domains