You can create a custom iPhone ringtone from most iTunes songs by purchasing the song for 99 cents, downloading it, choosing your start and end points using the iTunes software, then buying your custom ringtone from iTunes for another 99 cents. For details on this iTunes feature, read Dave Taylor. Chris Pirillo however, has a different method that bypasses paying iTunes and lets you create a ringtone from any song in your iTunes library for free.
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