You can find all the documentation in the next URL
http://www.oracle.com/appsnet/produc...ion/index.html

Like you, I have only few months(4) to be working with 11.5.8, I was afraid about all the things that I will need to know about Apps.

I suggest you to read the Concepts, the AD Utilities Procedures, AD Utilities Reference Guide and System Administration manuals.

HTH.

Best regards.