DocBook ( ) is an agreed upon SGML/XML DTD used for writing books and papers about computer hardware and software.

The home of DocBook: The Definitive Guide

Have a look at the wiki as well:

See also for a tool to convert DocBook formatted files into Texinfo or man page formatted files.

The docbook sf-project includes xslt and dsssl stylesheets. Normally that would be towards pdf, html, xml, rtf, but I would think tex as well, texinfo I'm not sure about. VL 16/6-03.

Online DocBook Validator and XML -> HTML/PDF Transformer:

A bit old but impressive list of tools about Docbook: includes many pointers to SourceForge-hosted projects (db2latex, etc.). CM 17/6/03.

I wonder if might help convert some docs into this format...