Hi
This LibreOffice-Kindle Extension might be of interest to people wanting to self-publish books to avoid needing to use a publishing house. It is proprietary and costs quite a lot until you compare it to the costs of alternatives.
http://www.kindletemplate.com/
It has not been extensively tested against LibreOffice but has been used with OpenOffice for quite some time. There might be an opportunity for a couple of people to get involved with testing and perhaps upgrading this for LibreOffice.
Regards from
Tom