Do you know those little arrows that appear in iTunes when you have a song selected? You know, the ones that appear just after the title of the song, artist, and album and link to the iTunes Store when clicked? Yeah, those! Well, if you want the arrows to link to your iTunes library instead of Apple's induced store (and another impulse purchase), then just type the following command into Terminal (found in Applications > Utilities):
defaults write com.apple.iTunes invertStoreLinks -bool YES
To change things back to normal, just replace the YES in the above command with NO. As some commenters have pointed out, you can temporarily reverse this hack by pressing option and clicking on the arrow.
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