Set individual ringtones to each contact in your address book for when you receive SMS text message on your Motorola Droid X.
1. Download and install Handcent from the Android Market. It’s free.
2. Open Handcent, then open an existing conversation. If one doesn’t exist for the contact you wish to set a ringtone to, make one.
3. Tap the icon in the upper-right corner of the screen that looks like a person with a gear.
4. Select Notification sound.
5. Select the ringtone you would like to assign to that contact.