The main idea of this post is to collect in a single place the links to the most useful resources for everybody who are interested in Oracle Access Manager 11g.   If you have something valuable to add to this list - just let me know.

Official documentation (Oracle Fusion Middleware 11.1.1.5):

• Administrator's Guide for Oracle Access Manager with Oracle Security Token Service - main guide for the  OAM 11g  administrator/consultant;
• Integration Guide for Oracle Access Manager - if you're in charge for setting up OAM integration with OIM, OAAM or OIF - that's a guide for you. Also has a chapter on WNA integration;
• Developer's Guide for Oracle Access Manager and Oracle Security Token Service - learn how to use Java Access JDK and develop custom authentication plugins;
• Oracle Fusion Middleware High Availability Guide, paragraph 8.8 Oracle Access Manager High Availability - set up HA for your OAM installation;
• Oracle Fusion Middleware Enterprise Deployment Guide for Oracle Identity Management - learn the best practices of the real-world enterprise deployments.

Useful Oracle Support documents (go to support.oracle.com to retrieve the contents of the documents):

• OAM Bundle Patch Release History [ID 736372.1]
• Install and Configure Advisor: Oracle Fusion Middleware (FMW) Identity Access Management (OAM, OIM) 11g [ID 340.1]
• Procedure to Upgrade OAM 11.1.1.3.0 to OAM 11.1.1.5.0 [ID 1318524.1]
• OAM 11g: How to Enable Oracle Access Manager 11g Server Trace / Debug Logging [ID 1298296.1]
• OAM 11g: How To Create and Configure Policies For Application Resources Without Using OAM Console UI [ID 1393918.1]
• How To Configure X509 Authentication On Oracle Access Manager (OAM) 11g [ID 1368211.1]
• OAM 11g WNA Step by Step Setup Guide [ID 1416860.1]

Blogs:

• Oracle Access Manager Academy from the Fusion Security Blog
• OAM Product management blog
• Oracle IDM blog

Books: 

• Oracle Identity and Access Manager 11g for Administrators