I came across a great series of video tutorials on YouTube covering the basics of NURBS, what they are, how they are created and how to manipulate them. If you want to broaden your understanding of NURBS curves and surfaces and not just use them without understanding what's really going on, then this is the series for you. Video one is linked below and while it does explain the mathematics behind NURBS, it does so in a way that's easy to understand. This series goes on to modeling in Rhino, but what's shown has applications to Plasticity. Here's the link for those who are interested: