A Gentle Introduction to Python is 100% free, just like all OpenCourseWare. Anyone can join, and you're welcome to share your work.
Pick up Python from leading innovators in online learning. MIT's chops. Codecademy's exercises. OpenStudy's study groups. P2PU's community. Need we say more?
Make friends with some smarties, and start programming from Week 1. Open for signup now, course starts June 2013.