Melton, J. Gordon
This was my go to book back when I first got interested in the genre. I recall late nights (before the internet grew beyond what Yahoo and AOL searches could yield). I would go in search of information though usenet and found a whole community of people that were interested in the same subject and shared their knowledge with me.
I suggest it as a reference guide for those that want to write about vampires and/or have an interest in the genre. Of course you could throw the guide out and make your own path.
Source: booksxyz.com