Searchable archive of the DocBook-Apps ML: http://sources.redhat.com/ml/docbook-apps/
Mark Johnson posted among others the following links recently on DocBook-Apps ML:
“The Gnome Documentation Project manual has links to templates you might find useful”: http://developer.gnome.org/projects/gdp/handbook/gdp-handbook/templates.html
Selfdocbook: http://people.redhat.com/twaugh/docbook/selfdocbook/selfdocbook.html
Nik Clayton contributed the following examples:
“All the FreeBSD documentation is in DocBook”: http://www.freebsd.org/docs.html
“The contents of http://www.freebsd.org/doc/en_US.ISO_8859-1/books/fdp-primer/ should also be very useful to you (in particular, section 4.2).”
Dan York contributed the following examples:
“Our (e-smith) user manual (done as a DocBook 'book) is available in DocBook SGML as well as HTML and PDF at:” http://www.e-smith.org/docs/manual/
“Also, the Linux Documentation Project makes available DocBook SGML versions of most all of the HOWTO docs:” http://www.ibiblio.org/pub/Linux/docs/HOWTO/other-formats/docbook/