If you are working with Wepsphere Application Server this is an excellent reference
The document contains sections on, Administration, Application Development, Architecture, Installation, Migration, Performance, Problem Determination Tools, and Security. Â Each section contains links to Learning documents, technotes, and troubleshooting references.
I found this via the IBM_appserver twitter account, a good one to follow if you are working with WAS.
Looking for the troubleshooting Guide for WebSphere Application Server ibm.co/gkO0CY #wasserv
— AppServer Support (@IBM_AppServer) March 19, 2012