You can find some really good Native American examples of cresting in the drawings of Steve Allely in the Traditonal Bowyers Bible series and also the two volume set of Native American Bows, Arrows, And Quivers by Jim Hamm and Steve Allely. I do this kind of cresting, using just black and red ochre. No cresting machine, I just have an oak block with a 3/8" rounded groove routered through it to use as a cradle to hold the arrow.
You can also use a candle to do some "flame cresting" that looks pretty snazzy.
