PayKickstart allows you to setup tracking IDs to the end of your affiliate links.
This is particularly handy when you are running multiple promotions for a product in many places, such as Facebook, websites, or an email list. It will allow you to keep track of where your traffic is coming from by using tracking IDs.
Take your affiliate link and add ?tid= then whatever the traffic source is.
For example: http://paykstrt.com/3043/137?tid=facebook
NOTE: You can monitor your tracking id related traffic metrics under "Reporting" >> "Traffic".