Geoghegan

I've been trying (without much success) to trace my Irish family. My grandmother Norah Geoghegan was born around 1903 but sadly I don't know where. I do know that she moved to London and worked in domestic service.  There she met and married my grandfather William Henry Hale. According to their marriage certificate Norah's father was William Geoghegan, occupation Farmer. 

My mother's memories of my grandmother were very sketchy as Norah died in 1940 when my mother was only 7 years old, but she always maintained that there was a family link with Lismore.

Does anybody have any knowledge of the Geoghegan family? I'd be grateful for any information, however small.

David Daniel