In the 1865 Norwegian census I find farms by the name 'Mælheim' in Hafslo district of Sogn og Fjordane. (Would that be close to Årdal in Sogn og Fjordane?)
There are quite a few farms named Hofstad/Hovstad near Trondheim (and in many other parts of Norway), in a good number of different districts/parishes near Trondheim.
So.... who were the persons you seek? First names, patronymic names (those end with datter or son/sen), vital dates of birth/death and emigration from Norway. Sometimes we can match the farm to the persons to find the correct location for your research. http://www.rootsweb.com/~wgnorway/good-queries.htm