Since no one has pointed this out yet there are a few pretty old and rather obscure myths/legends concerning vampires.  Silver hurts them, they have a bit of OCD concerning mustard seeds (this one from eastern europe) according to the myth if traveling around at night carry a pocketful of mustard seeds and if you are being followed by a vampire pull them out and scatter them on the ground the vampire will then have to stop and pickup every last one of them,  some other legends also state that vampires are super strong but not very quick so they can't pull the speedy gonzales thing on a victim, and most are rather stupid anyway.    However vampires posess differetn abilities depending on where the legends come from.

As for Shamans, umm think badass Druid mith a little Cheech and Chong and Jedi tendency towards vagueness and you will have a pretty good idea of what you are dealing with.  However when in doubt read the legends or talk to the local tribe (provided there is one near you) you can usually bribe a story from someone.