The process for creating custom alert tones is identical to creating custom ringtones. iOS 5 now offers the ability to select full-length ringtones as a text message alert. To create a custom Alert Tone, simply make a "ringtone" of the proper length (2-5 seconds) and select it as the text message alert in Settings/Sounds.
Italian Apple site Melaspazio.it [Translation] noted process was the same as creating ringtones. There are a few ways to create custom ringtones. The easiest option is a dedicated app like Ringer from Pixel Research Labs. This $3.99 app, available on the Mac App Store, creates custom-length audio-files directly from the iTunes Library, including fade-ins and -outs. It converts them properly and sends them directly to iTunes for syncing.
For users who don't want to pay to create a custom ringtone, there is a free option. Simonblog has the full instructions with screenshots, but here's the summary:
- Select a song in iTunes, right-click it and select "Get Info"If you're going to use a file as a text tone, be sure to keep it short or you'll be hearing 30 seconds of AC/DC's Back In Black every time you get a text. GarageBand can be used to create custom ringtones as well.
- Click the Options tab and use the "Start Time" and "Stop Time" to control the exact length of the sound file you want. Close the Get Info window.
- Right-click the song and select "Create AAC Version"
- Right-click the newly created song and select "Show In Finder"
- Change the file extension from .m4a to .m4r
- Head back to iTunes and right-click the newly created song. Select "Delete" and then click "Remove" to remove the song from the iTunes Library -- but then select "Keep File" so the actual ringtone doesn't get deleted.
- Finally, head back to the Finder and double-click the .m4r file. It will automatically add itself to iTunes as a Ringtone, ready to be synced with your iPhone.