I'm not quite sure I understand your question. Are you asking about sales made as a result of people clicking on your ads?
When people click the ads, they go to the website for that advertiser. Any sale(s) made will be captured by whatever software the website uses to capture that information.
Maybe if you posted again, and offered more detail around what you're asking, we could help you better?
Google AdWords Top Contributor
Those are some good questions from Theresa, the community will need a little more info to help answer your question there, but if you're looking for information on how to measure return on investment with AdWords, this link below might help you. http://support.google.com/adwords/bin/answer.py?hl=en&answer=14090
Hope this helps.