This is a miscellanious hodge-podge of good research books that didn't fall into any particular category.
VAMPYRES: LORD BYRON TO COUNT DRACULA by Christopher Frayling. 1991. Pub. Faber and Faber. ISBN 0-571-16792-6
Provides an overview of vampires from the early myths, through the European vampire scares, as well as discussion and examples of some of the more influential works of fiction. It also contains some very hard-to-find material including Dom Augustine Calmet's work "Treatise on the Vampires of Hungary and Surrounding Regions". Published in 1746, this work was very influential.
Also contains information on Bram Stoker's working papers that he created while preparing "Dracula".
THE COUNT OF SAINT GERMAIN by Isabel Cooper-Oakley. Rudolph Steiner Pub. 1970.
Anyone familiar with Chelsea Quinn Yarbro's many books about her vampire hero Saint Germain will be interested to find that she based her character on an actual historical figure. The real Count of Saint Germain lived in France during the 18th century. Extremely wealthy, he traveled in the highest social circles and was a figure of mystery; a person whose past was unknown. He always wore black and white, practised alchemy and told everyone he was centuries old.
This book is a compilation of the many letters, diaries and private records written about the Count by his acqaintances in the French aristocracy. It makes for fascinating reading.