Check out
https://www.google.com/support/adsen...y?answer=34028 Google themselves help you with ideas to help you with making the most out of your adsense... You might be having trouble because no one sees your ads.. maybe they blend in TOO well.. or you might have another issue where ppl are just not seeing them.
Also.. make sure you got all the code when pasting it in your site.. ppl might be clicking.. but if the code is wrong.. it won't do any good for you!.. lol