They are the ones most likely to have power/phone lines (though that is not guaranteed). Find the number here:
I called them after a different hurricane, and they were at least able to tell me the status of the neighborhood.
Salvation Army volunteers are assigned to attempt to locate individuals in affected areas that have personal requests for health and welfare status. It may take time to get a response, but this form is worth filling out.
http://qso.com/satern/emailfrm.htm