You have many PDF,ODT documents covering the writer, presentation, and calc functions -why is there not a document on using base?.
They are still creating the documents - if you go to the document foundation you can get the first chapter (finished) and the 2nd and 3rd chapters (draft copies but very helpful). Apparently while there are lots of developers working on the other guides we are lacking developers working on the base guide… I too am waiting for more to come… Anyone know when to expect more?
Links: https://wiki.documentfoundation.org/Documentation/Publications#LibreOffice_Base_Guide — LibreOffice FAQ - The Document Foundation Wiki — User Guide Tasks - The Document Foundation Wiki
If you understand german youfind a good BASE handbook here: http://de.libreoffice.org/hilfe-kontakt/handbuecher/
Check out wiki documents - that good German BASE handbook someone mentioned has now been translated and posted just this June 2013. I have already read half of it and have found it very helpful.
ODT/PDF
https://wiki.documentfoundation.org/Documentation/Publications#LibreOffice_Base_Handbook
(see also: Base 4.0 Handbook published)