A week or so ago, Google announced the availability of free online courses to learn more about AdWords. There are both live courses and 'on-demand' courses.
The first live online course is being given tomorrow, the 17th at 11am-12pm (PST) on Understanding Quality Score. You can sign up over here.
A Google AdWords Help thread has some more information on these courses. One person said:
I signed up for all three classes - even though I work with adwords daily I don't want to miss an opportunity to learn something new!
Forum discussion at Google AdWords Help.