I'm looking for tutorial notebooks on training and testing neural networks. I have a basic familiarity with Mathematica. Nothing more. I toyed around with a couple of neural networks that got better than baseline accuracy. I assume they would have been better if I understood available options and how to use them. The directed introductory webinars on machine learning and neural networks were interesting demonstrations of function capabilities but not much help in the how-to department. My hope here is to find tutorial notebooks that can walk me through the process of using Mathematica to train neural networks on some representative data, compare the effects of different parameters and are aimed at entry level folks like me.