Looking for Great-grandparents families

Great-grandmother Kari Gilbertson Born 1832, Great-grandfather Johann (John) Brenden (Johnson). Johan was born in 1824 and died in 1874 of pneumonia, just before family was going to leave for the United States. Last name Brenden, was changed to Johnson in the US. Kari and Johann had 10 children. area was Hadeland (??) in Norway. Any information would be great - seem to have hit a brick wall! Thank you