With The Rockley Report now available for free, I can point you to a case study about our use of DITA. DITA stands for Darwin Information Typing Architecture, an XML-based information architecture design originally from IBM but also an OASIS Standard with an open source toolkit on SourceForge also available.
This case study outlines our approach with a pilot project where we modeled both an error messages manual and an installation and configuration manual. A great read, and now the article is available with an optional registration. Enjoy!
Case Study: Using DITA to Develop a New Information Architecture at BMC Software