searching for Hansen/Bentsen family

My grandfather Hans Hansen was born in Skedsmo Norway. I am searching for his farm name and his mother karen's maiden name. also what happened to Nora and Marie. They stayed in Norway. The others emmigrated to the USA. Father: Hans Larsen Mother: Karen? Larsen b1830 d 1912? children: Nora Marie...married to Anton Hans b July 11, 1863 (my grandfather) Ludwig Karoline M Karen Dina b October,19,1874 Selma b....1867 My grandmother was a Berntsen, Benson or Bensen or Bentsen from oslo we think. Father: Anton Berntsen b July 8,1841 Mother: Gunild F. Gulliksen Berntsen b August 16,1842 Children: Annette b December 20, 1861 Martine b August 12, 1865 Bernhart Berntsen b July 1867 Anna b September 2, 1870 Kristine b December 15, 1870 (My grandmother) Karl Hendrick Berntsen b December 29, 1877 We believe that the Berntsen records may have been burned during WWII. Someone named Odd Nystrom??did help me with my grandfather Hansen 's side of the family but my computor crashed and we couldn't retrieve the information. If anyone has any idea about how I should go about searching for these family members and where they lived I would appreciate their input. I plan to visit Norway in 2007and hope to be able to visit the area where My grandparents came from Thank You Michael Ann Hansen Mortaloni