This week's book giveaways are in the Refactoring and Agile forums. We're giving away four copies each of Re-engineering Legacy Software and Docker in Action and have the authors on-line! See this thread and this one for details.
They have a competition about once a week and you can try out all the past competitions. I'm hoping to get back into it again myself. It's set up pretty well - they have system tests you can run to test your code so it makes for a great learning experience.