You probably know that you can use smart playlists in iTunes to filter your music. Say you want to find all your 5-star Grateful Dead songs; just create a Smart Playlist where Artist Is Grateful Dead, and Rating Is *****. You’ll get a list of all those songs.
But sometimes you may simply want to find a song in your library using rating information, and don’t want to make a playlist. All you need to do is type the name of a song, artist or album in the Search box, then type the number of stars (using asterisks or Shift-8) you want to use as a baseline. (iTunes runs a “greater than or equal to” search for the number of stars you put in the search field.)
If you add three stars (***), iTunes will show you any songs with three stars or more; if you want to limit the search to five stars, then type *****. So if you want to find your favorite recordings of Dark Star quickly, just type Grateful Dark *****, then enjoy!