Here it is a document which can help you. I've worked on this kind of device in Ultra High Vaccum 2 years ago. If you want more documents reply to me !
I forgot also this very interesting document on tuning fork by Franz J. Giessibl, the father of the tuning fork AFM. See p.8 of 35 to see photos of his tuning fork device.
Elvis,
nice applications you posted there but is there anything to say what tuning forc oscilators are? I have to start from scratch you know!
Thanks,
D.
If you want to know more about tuning fork itself (mechanics, electronics, resonance, how to use, how to drive), I advice to you these lecture notes of Khaled Karraï.