In hoodoo they are almost always referred to as doll-babies, and they can be made from a variety of different materials; most often people just used what they had at hand. So for instance you can use a barbie or action man or something similar, and personalize it with personal concerns.
Or if you make a cloth one, you would generally stuff it with spanish moss, and place appropriate representative materials at the respective places, Queen Elizabeth root at the pubic region for a female for instance.
People also sometimes use figurine candles, and treat them in a similar way.
But the most important part is the baptism, which is where you make the doll-baby the person it represents.