You might want to ask in the voodoo section of the forums.
I have only read one book years ago, but if memory serves there's different types depending on region, but there's New Orleans, Haitian, and African, that blends native religion and Catholic. They also use animals in their spells [chicken bones, cow tongue] that's about all I remember, but don't quote me. Good luck.
Side note, look up luckymojo.com