Ringtones are a fun way to personalize your iPhone. GarageBand, on every Mac, lets you create ringtones from music in your iTunes library.

Create a Ringtone Project
Launch GarageBand, select "iPhone Ringtone" (in the left column) and then double-click "Example Ringtone." Name the new ringtone project as you like.

Next, GarageBand will open the new project with a single track named "Jingles." In the track is a music snippet named "Pastel Slide Medium." Click on the snippet and press the Delete key to remove it.

Choose a Song
Click the Media Browser button (in the lower right corner of the window) and then drag a song from your iTunes Music library into the "Jingles" track. A bar with the title of the song will appear in the track.

Most songs are too long to use as ringtones. GarageBand uses a yellow bar (above the track) to let you specify an 18-second piece of the song to use.

Drag the yellow bar over the portion of the song you want to use for the ringtone. If you like, you can drag the ends of the yellow bar to create a longer ringtone. While the default 18 seconds is a nice length, 30-45 seconds is typical and let's you include more of the song.

Ringtones loop. So, if you let a  ringtone play long enough when your phone rings, it'll play again from the beginning.

Send Ringtone to iTunes
Select "Send Ringtone to iTunes" from the Share menu. GarageBand will convert and export the ringtone to the Ringtones library in iTunes. The next time you sync, the ringtone will be installed onto your iPhone for you to use.

Jam with your Mac using Magic GarageBand. Rock, Jazz, Country and other genres are available to help unleash the musician within you - whole songs laid-out by GarageBand to get your creative juices flowing.

On your Mac, launch GarageBand. (GarageBand comes with every Mac.) In the project window, click Magic GarageBand.

Choose a music genre.
Next, choose the genre of music you're in the mood to groove with. There are nine to choose from: Blues, Rock, Jazz, Country, Reggae, Funk, Latin, Roots Rock and Slow Blues.

Set the Stage.
Click the Audition button (or the Choose button). The stage will load and you'll see a virtual band, ready to play. You can connect an instrument to you Mac, or click "No Instrument". You can play along - "unplugged" - with a guitar or other instrument or sing along, instead.

Mix it up.
You can change the mix of instruments in two ways. Click on an instrument and then choose an alternate instrument (displayed just below the stage). Or, click on an empty part of the stage and then click the "Shuffle Instruments" button to randomly change all the instruments. Click the play button to hear the new mix.

If you'd like to edit the mix even more, you can click the "Open in GarageBand" button to open the song in Track View so that you can change, rearrange and add to the song anyway you'd like.