Everything you wanted to ask about the RHEL documentation but were afraid to can be found on the website of Red Hat:

6.0 Release Notes
6.1 Release Notes
6.1 Technical Notes
Cluster Administration
DM Multipath
Deployment Guide
Developer Guide
Enterprise Identity Management Guide
Global File System 2
High Availability Add-On Overview
Installation Guide
Load Balancer Administration
Logical Volume Manager Administration
Managing Confined Services
Managing Smart Cards
Migration Planning Guide
Package Manifest
Power Management Guide
Resource Management Guide
Security-Enhanced Linux
Security Guide
Storage Administration Guide
SystemTap Beginners Guide
SystemTap Tapset Reference
6.0 Technical Notes
V2V Guide
Virtualization

These documents can be found here.