Google Analytics - Perhaps the most powerful tool in Google's arsenal. Uncover loads of information about how the visitors from Google Adwords behave on your website. You can use this information to see which visitors left right away, which ones stayed the longest, and so much more. Before even setting up a Google Adwords account, I will install Google Analytics on the website that the Adwords traffic will be going to. Then, once Adwords is set up, I link it to Google Analytics. (To link them, go to the Reporting tab at the top of any Google Adwords page.)
