Surname Fonseth (Fønseth) in Norway

I am searching for Fonseth ancestors in Norway but have been unable to find anyone by this name in the Digital Archives. My husband's mother Myrtle Fonseth b. 1908 (in Canada?) was the daughter of Oscar Fonseth b. 1889 in North Dakota. Oscar's parents were from Norway. We have had no luck in identifying them. We assume they immigrated to Canada from Norway. Has anyone heard of this surname in Norway - what area? Thank you for any information. Kathy