Assign a tone to a Contact

If you want a unique ringtone for certain contacts, follow the steps below..

Access the address book, highlight a contact.
Press the Menu key.
Click Edit.
Click the trackball.
Click Add Custom Phone Tune.
Set a ring tone.
Press the Menu key.
Click Save.
FYI this tips only works with blackberry 8330 models. This feature may not work with your model.