What most people refer to as a Voodoo doll is what's called a poppet. They're commonly used for sympathetic magic. That is, they're a representation of the target. They don't work like TV, such that pricking one with a pin will cause physical harm to the person it represents.
Rather, they can be used as a focal point representing the target, such as sending energy, piercing with a pin to represent man different things, and even using for divination purposes. People who use them find them a good tool for distance work.
Sorry for going off on a trail there. I hope the word 'poppet' helps you find what you're looking for. I've never gone that route myself.