FAMILY HISTORY OF MITHUEN'S AND MATHISON'S

Hi everyone, Hopefully someone out there can help my sister and I. We are trying to do the family history on the MITHUEN'S and the MATHISON'S. We know that both families are orignally from Norway, but we don't know the farm name for either of them, or the whereabouts of the original family homes...............or what cities they originally came from. So if anyone out there could help point us in the right direction, or if you know the farm name, or the cities................it would be greatly appreciated. If this would be any help, here are our grandparents names, however we do not have our great-grandmother's maiden names, or the year they were married to their spouses, or the year they travelled to America, but we do know that they made their new home in America.............in the state of Wisconsin..............one in a town by the name of Brookville and one in the town of Spring Valley. Hopefully this is something someone will remember, or may even have some letters that were written home(Norway) and may have even mentioned their names. The names are as follows: MITHUEN: Iver or Ivar married Carrie Knutson, and MATHISON: Ole married Aagot. We are interested in anything that sounds close to the names and spelled close to the names.