http://www.cgcircuit.com/tutorial/rigging-in-houdini-kinefx

Complete and comprehensive rigging course for the new Houdini rigging system - Kinefx. Learn how to create an advanced reverse foot rig for the leg. You will start from the beginning by learning to properly create, orient, and manage joint hierarchies in Houdini.  You will learn how to create FK and IK setup with proper blending. How to organize your rig network and how to break it down into smaller HDAs.  Walk step by step with the author through the rig debugging process. Learn how to create debug HDAs to better visualize rig data.  It’s complete training for people with None to Intermediate knowledge of rigging in Houdini. Autor presents a great number of useful Tips and Tricks which advanced TD will find useful.