Toon Generations Toe Control

I'm playing around with the Toon Generations figures, which are fun for a cartoon-like project I'm working on. They work well, except for certain still shots I am looking for, I need to be able to manipulate the feet a bit more. The TG figures have a right and left foot, and a singe "toe" to control the front of each foot.
I'm not sure what I would need to do to give myself more control. My thought was (but I am pretty new at this so I might have this wrong) to make new bones for each toe. I'm not sure how to do that. I looked at some tutorials for adding bones to a new model, but this isn't exactly that. Is there a way to add new bones to an existing skeleton? Or is that not the right approach?
Any thoughts would be much appreciated.
Thanks!
-Ben