Ah, I use to have a chart that showed good and bad places for Adsense ads.
Ads in the footer are the worst possible place.
Blend the ads in with the website, and people tend to click on Blue links more often. You know, just that regular blue.
Position it in spots that people will be clicking frequently around, for example, menu or navigation, in between posts, etc...
I think I did a pretty good job with the position of the ads on my site if you want to check it out. http://www.talkmusicforums.com
I have a set under the User menu, along with the sidebar. (Had more success with the larger banner ads at the top of the page, under the navigation/menu, but I replaced it once I made the sidebar. I'll probably move it later)
The payout limit is a *****, $100 is a way too ****ing much. It used to be $50.
EDIT: Found one:
White = Worse
Then the darker the orange, the better. Obviously having ads before/after/in the content is extremely effective.