A couple of years ago I bought Andrew's book "21 Ways to Maximize ROI on Google Adwords Select" written in 2004 for $69 and never looked back. What a great tutorial! Now you have a great opportunity to download a free updated ebook with all the information of quality score and other things that Google implemented within the last few years. I jumped right on it and downloaded myself a copy and I suggest you do the same. Even if don't do any AdWords campaigns right now - keep it in your reference file for the future, because Andrew Goodman is one those people you want to listen to about how to advertise with AdWords and be successful.
So, here is a link to download Google AdWords: A Brave New World buy Andrew Goodman.
P. S. in case you are wondering - no, I'm not getting paid for this post.