On that link, where it says "Go to Application"...right underneath it says "Block Application" Click it
Livejournal is doing the same thing too, I blocked it. Seriously, I could care less who reads my stuff since most of it's friends only anyway.
In case anyone cares: "How does this work? This application ranks your friends based on how often they interact with your Facebook wall. Interactions counted include wall posts, comments, likes, gifts and other public items posted to your wall. In accordance with the Facebook Privacy Policy, we do NOT count page views or private messages." The app is still called Stalker Check, but now they call your stalkers "fans." hahahaha