Wiblemo

I am trying to find information about Gunder Wiblemo, and am not sure where is the best place to search. I have only a few facts. He was born in Mandal, Norway 12 Apr 1880. He emigrated to the U.S. from Kristiansand on a Thingvalla liner, arriving here about 1 April 1897. He first settled in Decorah, Iowa, then in Parker, SD. He remained in Parker until his death. Family tradition is that his surname before emigration was Aanensen or Amendsen or something that sounds like that. I would like to know the name of his parents. I have located a family - Thor Wiblemo - living in Mandal today. They have no idea if we are related, and since I don't speak Norwegian, I'm not sure how to ask them the right questions. Any suggestions where I should begin my search?