Hayhoe family

HI there, I'm just beginning to trace my grandfathers side of the family, and I'm looking for some help or clues on where to start.My grandfather's name is Raymond Edward Hayhoe and he married Gladys Ann Rice.I know that he has a couple of sisters out there, but I'm not sure of their names.Both he and my grandmother settled in a little town in Maryland.IF anyone has something of interest please email me.Thanks.Michele