It’s a common question for Internet marketers that- Where should I place Google ads on my pages?

The answer lies in “Heat Map”. The concept is based on -identifying the place on the webpage where visitors click most as their eye sight concentrate on those locations. A map is generated based on the data of user clicks. This is called Heat Map. This heat map suggests which are the most clickable regions on a particular web page.

Read a good article on “Google Help” to know -Where should I place Google ads on my pages?

https://support.google.com/adsense/?hl=en
Wikipedia also has a good article on heat map here:
http://en.wikipedia.org/wiki/Heat_map

Finding on Google will also lead you to few good articles and resources on Heat Map:

http://www.google.co.in/search?rlz=1C1GGLS_enIN347IN348&aq=f&sourceid=chrome&ie=UTF-8&q=heat+map

heat map

To Analyze your pages, what are the hot & click-able zone on your page, you can use some free and open-source solutions. On of them is ClickHeat from labsmedia.com

http://www.labsmedia.com/clickheat/index.html

One another good solution is from heatmapapi.com and can be found here:

http://www.heatmapapi.com/

It has Java script and dot net based solutions.

Hear is a sample use of the API:

http://www.heatmapapi.com/Sample_Google2.aspx