'How to Prepare Active Directory and Domains
http://www.microsoft.com/technet/prodtechnol/exchange/e2k7help/8e8464df-2d1d-4d68-82de-b0c158c549c3.mspx?mfr=true

'Upgrading to Exchange 2007
http://www.microsoft.com/technet/prodtechnol/exchange/e2k7help/a313c016-0e51-466e-a3de-953e1e0d347d.mspx?mfr=true

'How to Install Exchange 2007 in an Existing Exchange Server 2003 Organization
http://www.microsoft.com/technet/prodtechnol/exchange/e2k7help/8e8464df-2d1d-4d68-82de-b0c158c549c3.mspx?mfr=true