Pedersdatter/Nilson to USA

I'm told my great uncle's (Peder Rasmussen) daughter, Johanna PEDERSDATTER, and son, Per MAGNUSSON came to America in 1880. Also, Lars NILSEN, who was married to Johanna. I don't know if they married in Norway or here in the States. Their destination was Dalton, Minnesota, Is there anyway I can find information on them? I'd sure appreciate it. The farm name was either Misaloen or Sagmoen for Johanna. Thanks! Juanita Smith E-mail:[email hidden]