I only have one set, which is in very good condition.  I only know of a very few complete sets, and don't know of any for sale.

Herbertia is the Journal of the International Bulb Society.  This society started life as the American Amaryllis Society, and changed to the Plant Life Society, and is now IBS.

It is a fantastic source of information for those loving bulbous plants.   You will find a rare combination of scientific research, and hobbyist contributed articles.  Here is information bound to be useful for any serious bulb enthusiest.