Ah HA! Found it. Attached is a video that explains it better than my text will.
Basically, you need to navigate to "Apps" in iTunes (listed under "Library). Find the app whose iTunes page you want to locate, click that tiny grey little circle with the arrow on it, and select the name of the app from the dropdown menu. It will take you to the app's official itunes page with the screenshots, reviews, etc.
http://vimeo.com/27826122