I am happy to inform you about a new ebook that we published online. Although the book is in Serbian it is one of the older works.
You can find more information at : http://www.rodoslovlje.com/phorum/list.php?56
This book is a 19th century work by Stojan Novaković on Serbian Heraldry and references about heraldry amonst Serbs. The book is in Serbian and holds some nice facsimilies.
Other works are being worked on.