Fellow collector/dealer Gabe Konrad has just released a 23 page well illustrated catalog of bookplates, bookseller labels and books about both subjects. It is an excellent reference for both beginning and advanced collectors.
Here is a link
http://bayleafbooks.com/uploads/eList_17.pdf
--------------------------------------------------------------------------------------------------------------------------Fellow Collector/dealer Jacques Laget has just released his catalog of 110 new bookplates
http://www.ex-libris-jacques-laget.fr/