If you are planning to deploy the Exchange 2010, I would suggest to download the Microsoft Exchange 2010 Build guide from TechNet site, this guide also help you to prepare formal deployment document for Exchange 2010 Server. (CAS/HUB/MBX and DAG).
Download from here: http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=5f9dbd88-dadf-4ad9-9f28-ad35a1ab1da2