How to select a submersible motor?

I have drilled a new borewell for 6 inch diameter and 150 feet depth in my agriculture land two days back. Water level is available at 90 feet itself. Presently I have 2 phase supply and I have also applied for 3 phase supply. How can I select my submersible motor? I am planning for 3 inch delivery.
So how many hp submersible motor-pumps are required? Also, how to select stages in motor?