You can snap up a copy of Dudley Wright's Vampires and Vampirism (rev. ed., 1924) for US$160.
I'd buy it myself if I had the available fundage!
From a critical perspective, the work is pretty shabby (you can get a variety of reprints of this book, to see for yourself), but it still serves as one of the seminal entries in vampires studies of the twentieth century.
The original edition was published in 1914 and helped filled a gap in vampire studies at the time, which was primarily occupied by occultic articles and works like A. Osbourne Eaves' Modern Vampirism: Its Dangers, and How to Avoid Them (1904), a treatise on psychic vampirism.
Montague Summers was brutal in his review of Wright's work, noting
it were not an easy task to find a more insipid olio than Vampires and Vampirism, of which the ingredients, so far as I am able to judge, are most palpably derived at second, and even at third hand.But one wonders if Summers would have made his own contributions to the genre, if it hadn't been for Wright stepping up to the plate.