Milo,
I used a combination of green and light-brown Fiebing's leather dye. I applied coats of each dye separately and sanded/steel-wooled until I got the color I was looking for.
This bow was really just practice before I tackle the piece of wood I really have my eye on. It is full of bumps, knots, character and even has some branches coming out of the back. I figure I have about a 50/50 chance of pulling it off.