The full set of Office Communications Server 2007 R2 documentation is contained in the download file named Communications_Server_2007_R2_Documentation.chm.
IMPORTANT  See Additional Information for important information about circumstances under which a CHM file will not display correctly, and how to resolve the issue.
Selected, high-value sections of the documentation are also provided as separate Word documents.

These file are included in the download

• Communications_Server_2007_R2_Documentation.chm
• OCS 2007 R2 Deploying Archiving Server.doc
• OCS 2007 R2 Deploying CWA.doc
• OCS 2007 R2 Deploying Dial-In Conferencing.doc
• OCS 2007 R2 Deploying Edge Servers.doc
• OCS 2007 R2 Deploying Enterprise Edition.doc
• OCS 2007 R2 Deploying Enterprise Voice.doc
• OCS 2007 R2 Deploying Group Chat Server.doc
• OCS 2007 R2 Deploying Monitoring Server.doc
• OCS 2007 R2 Deploying Response Group Service.doc
• OCS 2007 R2 Deploying Standard Edition.doc
• OCS 2007 R2 Getting Started - Documentation Roadmap.doc
• OCS 2007 R2 Getting Started - New Client Features.doc
• OCS 2007 R2 Getting Started - New Server Features.doc
• OCS 2007 R2 Getting Started - Technical Overview.doc
• OCS 2007 R2 Getting Started - Uniified Communications Glossary.doc
• OCS 2007 R2 Migration from 2005.doc
• OCS 2007 R2 Migration from 2007.doc
• OCS 2007 R2 Planning.doc
• OCS 2007 R2 Preparing Active Directory Domain Services.doc
• OCS 2007 R2 Supportability.doc
• OCS 2007 R2 Upgrading the Evaluation to Full Released Version.doc

Download documentation here:
http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=e9f86f96-aa09-4dca-9088-f64b4f01c703