Why? Because Lady Blacksteel has been known to play a vamp PC a time or three)
This is the "Vampire PC Book" for Pathfinder and it covers exactly that.
- There are notes on running vampires as PC's, the biggest of which is "it's not a great idea but here are some ideas on how to make it a little less broken". My own take on it is that if you're starting a campaign at 1st level, sure, it's a terrible idea. If you're starting one at say 10th, well, that might work.
- The main focus is on the Dhampir, which is basically Blade - one parent is a vampire, one is not. This lets them manage the power level to the point that it's equivalent in power to the standard races while still keeping most of the flavor of a vampire type character. I originally thought it was a stupid idea but I've come around on it and there are enough good ideas here that I can see it being a pretty interesting character to play.
- The book describes 4 different sub-races of vampire, branching into Asian, Indian, and the Nosferatu in addition to the more traditional Dracula type.
- There's a lot of information on how the various races and the dhampir fit into Golarion as well so it's not all about the mechanics. From deities to areas of influence it's plenty to get the wheels turning without overdoing it.