This older thread touches on the topic a bit. You should contact your utility company for the emergency plans for your own community since they vary. E.g. some places may only do TV/radio broadcasts, some places may add sirens, have police or fire go door-to-door, some places may do automated "reverse-911" telephone calls to every affected neighborhood, etc.

Just a hunch, but the website for your utility company, or maybe even the front of your telephone book may contain a section on what to expect and do in a situation at your local nuclear power plant.