If you don’t like the DROID! sound that the Motorola Droid makes when you receive a text message, you can silence or change the ringtone with these steps.
1. Tap the application slider.
2. Tap Messaging.
3. Press the Menu button.
4. Tap Settings.
5. Scroll all the way down and tap Select ringtone.
6. Tap a ringtone or select Silent.
7. Tap OK.
If you like, you can tap Vibrate.