Stalker Tracker and Profile Tracker (Facebook apps? apps might be too generous) are just scammy products; there is not any app that can show you who has viewed your profile. Facebook probably knows, but you don’t. Pages can see how many views and other basic website statistics; individual personal accounts currently display no statistical information (at this point – although it is bound to be collected by FB).

Facebook’s statement on profile tracking:
http://www.facebook.com/help/?faq=14357

Facebook does not provide applications or groups with the technical means to allow people to track profile views or see statistics on how often a particular piece of content has been viewed and by whom. If an application claims to provide this functionality, please report the application by going to the application’s About page and clicking “Report Application” at the bottom of the page, or by clicking “Report” at the bottom of any canvas page within the application.

Facebook’ statement on unfriending: “Stories will never be published about: …People you remove from your friends.”

About the only way to see who unfriends you is to install Greasemonkey (a Firefox addon) and use a third party (javascript) that tracks who unfriends you, considering that it is not retrospective, it probably just keeps track of your friends starting from the time you install it. It is also Firefox specific, too. You can find info about that here

You can read more about the scam app for profile tracking here 

To get rid of these from a facebook account:

Account>Privacy settings>Apps and websites>

You can view the list of apps you have authorized (Click edit)

Also two choices are featured up front:
Remove unwanted spammy apps

OR in a worst case scenario you can turn off all platform apps, but then you’ll need to reauthorize the ones you want use.

You can also search for specific apps: 
Click edit to see what they have access to and make changes as appropriate.