Missing PWM module Beaglebone Black

I believe that the PyBBIO library has been written to support the 3.2 kernel. With 3.8, everything has been changes to support the new the device tree layout. If you poke around these forums you’ll find that things aren’t very stable and so it’s hard to find very many working libraries. You can either downgrade to the 3.2 kernel (I don’t know how to do that), or search for a blog post from a brave hacker.