Sounds like a charging issue, you were running on alternator power until you shut it off then nothing, because the battery is stone cold dead.
I would start at the simple things, is the alterternator charging when running? All the wires connected to it and the regulator?
Charge the battery, start it and begin knocking things off the list..
If you post a general location where the car is (tomorow), there may be a member that can help you..