Last update on 30/08/2009

Latest updates and hotfixes:
July OCS Updates

Deployment media:
Office Communications Server 2007 R2 Trial
Office Communications Server 2007 R2 Group Chat server
Office Communications Server 2007 R2 XMPP Gateway
Office Communications Server 2007 R2 UCMA 2.0 Speech Language Packs
Office Communications Server 2007 R2 Resource Kit Tools
Office Communications Server 2007 R2, 32 bit PreCallDiagnostic Resource Kit Tool
Office Communications Server 2007 R2 Web Scheduler – see this post on how to install
Planning Tool for Microsoft Office Communications Server 2007 R2
Edge Planning Tool for Office Communications Server 2007 R2
Office Communications Server Public IM Connectivity Provisioning Guide
Office Communications Server Public IM Connectivity Provisioning Site

Desktop client installation media:
Office Communicator 2007 R2 Trial
Office Communications Server 2007 R2 Attendant
Office Communications Server 2007 R2 Group Chat client
Office Live Meeting 2007 client and addin
Recording Converter for Microsoft Office Live Meeting 2007
Agent Communications Panel for Microsoft Dynamics CRM 4.0
Messenger for Mac 7.0.2

Mobile client installation media:
Office Communicator Mobile 2007 R2 (SmartPhone)
Office Communicator Mobile 2007 R2 (Pocket PC)
Office Communicator Phone Edition 2007 R2 (Tanjay)
To install directly on the cellphone and get java client, use http://getcomo.com

Testing, Training and Troubleshooting Guides:
Office Communicator 2007 R2
Office Communications Server 2007 R2 Group Chat
Office Live Meeting Client for Office Communications Server 2007 R2
Unified Communications Adoption and Training Kit 2007 R2
Unified Communications How-To

White Papers and Technical Documents:
Microsoft Office Communications Server 2007 R2 Technical Documentation
Microsoft Office Communications Server 2007 R2 Deploying Certificates White Paper
Microsoft Office Communications Server 2007 R2 Site Resiliency White Paper
Unified Communications Phones and Peripherals Datasheet
The UC White Paper
Configuring XMPP Gateway with Jabber XCP 5.4
Configuring XMPP Connectivity to Gmail
OCPE Device (Tanjay) Upgrade Guide

Post was based on a great post by Aaron Tiensivu: http://blog.tiensivu.com/aaron/archives/1834-My-collection-of-OCS-2007-R2-information-official-MS-download-links-only.html