You'll find here the archives which contain all the material I used to build my pdf, epub and xhtml files.
There are here the xml files (Docbook 5), the images and the sounds.
What you will not find here are the original documents which you can find on the websites mentioned on the individual pages of the different projects.
For people who prefer to edit stuffs in office suites (Windows office, OpenOffice, LibreOffice or others), there is a simple way to get the document: load the xhtml file in a browser (I tested Firefox), select all the text (Ctrl-A), copy (Ctrl-C) and copy it in the office writer window (Ctrl-V). That's all: not everything will be ok (formatting to adjust), but most of the work will be done.
The xhtml files with images/sounds:
The xml, xhtml files with images/sounds: