When you select a song in your iTunes library, a small drop-down menu appears that gives you access to the song, its album, and the artist in Apple's iTunes music store. For some this may help them complete albums and find music, but for others the direct commercial links may not be welcome and they might wish to remove the store links from their library.
To remove the menu you just need to open the Terminal application and run the following command:
defaults write com.apple.iTunes hide-ping-dropdown -bool TRUE
While doing this will remove the menu and its links to the iTunes store, the menu does have a beneficial side. When you are playing a song in iTunes such as that on a randomized playlist, you might often want to hear more songs from that particular album or artist. If you hold the Option key when clicking the store link menu, instead of searching the store iTunes will reference your library and bring up songs and albums you already own.
This feature was the original use of the links in past versions of iTunes, but while Apple has made it a secondary option by requiring you hold the Option key to access it, you can reverse this behavior so searching your library is the default behavior and holding the Option key brings you to the iTunes store. To do this, open the Terminal and run the following command, followed by relaunching iTunes:
defaults write com.apple.iTunes invertStoreLinks -bool TRUE
In addition to inverting the store links, you can also restore the previous arrow links instead of using the menu, which will give you a more direct one-click option for revealing items in your library. iTunes still contains the code for the older links, so you can run the first command above to hide the drop-down menu and then execute the following command to reveal the old iTunes arrow links:
defaults write com.apple.iTunes show-store-link-arrows -bool TRUE
To undo these modifications, you can repeat them and use the opposite boolean value (ie, FALSE instead of TRUE), or you can delete these settings from the iTunes preferences by running the following commands:
defaults delete com.apple.iTunes show-store-link-arrows
defaults delete com.apple.iTunes invertStoreLinks
defaults delete com.apple.iTunes hide-ping-dropdown