Google announced a couple of days ago that its AdWords program now can be configured to provide you with a report that details the performance of your ads hour by hour, so that you can judge the best time of day to run your ads more easily. Although data on hourly performance only is back-dated to February of 2006, this new reporting aspect should help you confirm or deny your wisdom in any day-parting selection you may have made for showing your ads. Details:
Hourly reporting allows you to see impression, click, cost, CTR, and average CPC data for your entire account or specific campaigns on an hourly basis a�� on either specific calendar dates or across a designated time period (such as Last Week or Last Month).
Visit the help area for AdWords Reporting for FAQs and info.