From page 96 pf your user manual: http://cache.vzw.com/multimedia/mim/samsung-gusto-3/basic-samsung-gusto-3-ug.pdf
1. From the Home screen, press the Left Soft Key Menu ➔ Settings ➔ Sounds ➔ Call Sounds.
2. Use the Directional Key to select a setting, then press SET:
• Call Ringtone: Select from a list of pre-loaded ringtones, or choose Get Ringtones to find and download new ringtones.
• Call Vibrate: Choose On to select a vibration pattern for use with the Call Ringtone, or select Off.
• Caller ID Readout: Choose Ring Only to have the phone play the Call Ringtone for incoming calls. Choose Caller ID + Ring to have the phone announce the caller ID, plus play the Call Ringtone for incoming calls. Select Name Repeat to have the phone repeat the caller’s information for incoming calls.