I've just launched a new PPC ad tracking service designed specifically for Clickbank affiliates. http://www.cbadtracker.com/ Basically, the tracking technology generates a unique tracking ID based on the PPC Ad Network and keywords used and then passes it on to Clickbank as their TID. Sales data can then be imported from Clickbank to generate reports that make it easy to quickly identify underperforming keywords so that you can delete (or refine) them from your ad campaigns. If you are not currently using the Clickbank TID parameter, this can provide you with the information you need to improve your performance. Currently offering a 14 day free trial, followed by very affordable rates ($0.002 per click).