iTunes 7 and later contain an option called MiniStore. This MiniStore provides you with similar music or video choices based on the items currently selected in your library.
The first time you launch iTunes 7 the MiniStore displays a message that explains the MiniStore and asks you if you would like to turn it on. The MiniStore is not enabled until you click on Turn On MiniStore
Once enabled, you can show or hide the MiniStore by choosing Show MiniStore or Hide MiniStore from the View menu.
The MiniStore works like this, iTunes sends data about the item selected in your library to the iTunes Store to provide relevant recommendations. When the MiniStore is hidden, this data is not sent to the iTunes Store.
If you have an audiobook or TV show selected in iTunes, you'll see the top audiobooks or TV shows in the MiniStore. If there's not an iTunes Store available for your country, then you will see content for the USA.
You can disable the ability to show the MiniStore by disabling the iTunes Store in Parental Controls. Click here for steps to do that.