How to Change a Ringtone for a Specific Contact in your Android Smartphone:
1. Go to "Contacts"
2. Find specific Contact you'd like to assign a special ringtone
3. Press your "Settings" button
4. Go to "Options"
5. Go to "Ringtone"
6. Complete action using Android System or what ever Ringtone App you have.
7. Select the ringtone you want to assign to that contact.
8. Complete by pressing "Done"
I'm sure you've discovered how to do this by now. I hope these step by step directions help somebody...