For your information, you will find the whole family in the Norwegian census of 1900 at this URLhttp://digitalarkivet.uib.no/cgi-win/webcens.exe?slag=visbas...
The farm was obviously in Vestre Toten commune, but perhaps the closest township was Lena. On the same webpage you will find an emigrant database. Look in emigrants over Oslo harbour, which would have been the most obvious place for them to leave Norway.
For further assistance you may try the local historic and genealogical society athttp://www.slektshistorielaget.com/