Google AdSense Add-on's
While the reporting provided by Google for the AdSense product continually it may not provide you with enough statistcal information to optimize your AdSense revenue. While still limited in number a few packages exist to provide improved AdSense statistics.

AdSense Tracker
AdSense Tracker is a PHP based software product written by Jonathan Leger. You can find more information on the product as well as purchase it at the AdSense Tracker page.

We like AdSense tracker because it provides the following additional statistics and features:

AdSense Tracker suggests what kind of content to build.
AdSense Tracker suggests which ad formats and color combinations work best.
AdSense Tracker suggests which search engines and keywords to optimize for.
AdSense Tracker provides stats in real-time.
AdSense Tracker suggests what ads your visitors are clicking on.
AdSense Tracker tracks an unlimited number of domains.
AdSense Tracker gives you real-time tracking of your AdSense channels and your own custom channels.
AdSense Tracker tells you the click-thru rates and totals for each directory and subdirectory of your website.
AdSense Tracker gives you detailed information about every click.
AdSense Tracker lets you search for specific pages, referrers or keywords.
From what I understand the product now provides support for AdSense for Search.

Adsenselogger
If purchasing a commercial product is currently outside your budget you don't have to feel left out. Thanks to the "first ever, public released open source php adsense tracker" you can gain many of the features of other AdSense trackers without the cost. The following excerpt is from the homepage of Adsenselogger.

In short, the purpose of AdsenseLogger is to track the owners clicks and impressions on Adsense Ads across multiple domains. The Adsense ad tracking registers amongst others : Adsense ad colours, referrers, details about ad clicked, ad size, ad type and much more data that will assist in optimizing Adsense earnings.

Sounds good to us!