Oppland Immigrant info

Everyone's been so helpful I thought I'd throw out a family mystery and see if anyone can provide leads. My gg-grandfather Johannes Augustus Pedersen was born 1839 at Lillemalterud Farm, Aas Parish, Vestre Toten, Oppland (christened 09 Jun 1839). He came to America in 1867. I am trying to find out if his wife Kari/Karen Gilbertson (Gulbrandsdtr?) came with him or if he came alone. I know nothing about Kari/Karen and am very curious to locate where she was from in norway. I do know that she was born 28 Dec 1838 and imm. in 1866/67. Her father was supposedly Gilbert Johansen (Gulbrand?). I would really appreciate any help or guidance with this one because we have been looking for quite sometime. Kind Regards, Mike