Dark Neighborhoods. The Dark Journeys Trilogy, #1

They are here -- the shape-shifting entities that can find you in your neighborhood, in your past, and even in your dreams. Dr. Harper Paget, whose ancestors have been at war with them for generations, comes to Atlanta from a university in Ilinois where he is a mythology professor to investigate other hauntings; he discovers that they are here in this community because of him. In ancient Greece, they were able to manifest as creatures known as the Lamiae, and in modern-day Indonesia, they have taken on the appearances of deadly creatures known as Kuntilanak.
Harper's publication exposing them to the world and an ability he inherited from his grandmother is a deadly threat to him and to all of those around him.  Be careful of what you search for .