I just thought I'd give something back to the community. This is not a free method, and it requires a bit of effort. When you are an AdWords Qualified Individual (get the Google certificate), every 12 weeks you get 20 vouchers of $100 (or local currency). You can view the requirements to participate in the program right here. Basically you study AdWords, pass the exams, which costs $50 to take and you get your vouchers mailed to you 4 times a year. You can take the exam right here. You'll have to study a bit, or open up AdWords on a different computer when you're taking the test. It's not that easy, but well worth it. You can study everything about AdWords that you need for the test right here. And a bit more info about the vouchers when you've passed the test. Most of you won't even bother, because you actually have to study a bit and invest a bit of money (wow $50 to get $8.000 back in vouchers), but some of you might find it useful.