Unless you are familiar with your home's wiring, contact an electrician. If you are comfortable with replacing receptacles, to begin, TURN THE BREAKER OFF. Remove the outlet that you believe is the most likely to be first in the circuit. Cap the wires. Turn the breaker back on and test the other outlets. If you chose correctly, all the others will be dead. If you chose incorrectly, put the original outlet back in and try another and repeat the process.