The Documentation Team has published the LibreOffice 4.3 Draw Guide. Free PDFs can be downloaded from The Document Foundation’s wiki. Printed copies can be purchased here. (Published by Friends of OpenDocument Inc.)
The LibreOffice Documentation team has published another book: the LibreOffice 3.4 Draw Guide. Individual chapters and the full book are available on the wiki. A printed copy can be purchased here. Other books for v3.4 (Impress Guide, Calc Guide, Math Guide) in various stages of completion are also on that wiki page.