I'd like to offer one more trouble-shooting tool: a 3-wire extension cord plugged into a known-good receptcale. This gives you a reference hot, neutral, and ground to carry around with you as you use your tester.
As for the tester, I highly recommend a solenoid-type rather than a regular volt-meter, because the latter usually has such a high input impedance that induced voltages from nearby wiring can give you a false hot reading.
