My start with LibreOffice goes back to StarOffice, which became OpenOffice.org, from which LibreOffice split. To learn OpenOffice.org (OOo), I subscribed to mailing lists and then tried to answer every question that I could. The questions that were less frequently answered were related to Macros, so I concentrated on those.
If you spend time on a mailing list or forum, you will find that the same questions are asked over and over again. To help me remember what questions had already been answered, I started a document titled AndrewMacro.odt containing all of the examples that I could find. The document was never intended for public use.While answering a question on a mailing list I mentioned that I had the solution in a document of examples and I was asked to post it.
Since that time, the document has grown to contain more than 500 pages. Different versions of the document have been translated into a few different languages. I never changed the general format or the order of the macros so that it would be easier for translators to add newly added sections.
Many of the examples in the document were provided by the general community. Other community members have provided fixes and corrections. At this point, there have been so many contributors that it would be difficult to identify all of them.
The official documentation group is always in need of help, and it is a great way to learn a bunch about how LibreOffice works. So, even if you know nothing about macros, you can help with document about almost any topic (see http://www.libreoffice.org/get-involved/documenters/).