Badi Jones has written a couple of great articles about how to use google adsense to monetize your site:

Getting Over the $100 Adsense Hurdle: Talks about the process that one has to go through to get past your first hundred bucks with adsense. I read it and thought, man, this article was written for me. Very encouraging, specially if you are going through one of those phases where you feel that everything you do to monetize your site(s) is worthless.

Want to Boost Adsense Earnings? Then Start Testing: Talks about what you can try to do to increase your adsense earnings by experimenting with ad location, format and colors, and keeping track of them by using adsense channels. It’s a mini tutorial for Wordpress users as you’ll need a page that can execute PHP (however a javascript example has been included for other users).

Very useful stuff. At least for the little guy, like me…