I want to design a book using LibreOffice. Is there somewhere on the net good tutorials for this?
See Philip's comment. LibreOffice is just not a tool for book design. It is a tool for book authoring, and lacks almost all the tools necessary to design a book.
Keep in mind that there are two quite separate things you must learn: book design, which is an entire and very mature subject; and the particulars of how to use whatever software you are working with. You don't become a book designer by learning how to use a layout program, and learning how to design a book doesn't necessarily teach you about any particular application (but it will tell you why LibreOffice is not a suitable tool for the job).