I know I've responded before, but in the course of my research have found a LOT more information. Carl Elstad was born in Alvsborgs Lan, Sweden. His parents were Johan Laurentius Oskar HELLSTADIUS and Hulda Eugenia ROSENBLAD. (ELSTAD, HELLSTADIUS, HELLSTROM all being variants of the surname I have seen so far in census and church records). I have searched both Swedish and Norwegian census and this is the only Carl who fits all the known data. (I've also seen an immigration recird for Carl Elstad which suggests that he is the same Carl whose surname is recorded as HELLSTADIUS in the Swedish census.) Carl married Helga Benedikta Teresia LINDELOF in Minnesota. Helga was born in Bjuv, Malmohus Lan, Sweden 21OCT 1895. Her parents were Johan Melcher LINDELOF (b. 1872 Nas, Malmohus Lan) and Betty Albertina JOHANSDOTTER (born 1873, Stehag, Malmohus Lan). (Betty's father used the surname JONSSON, his father being named "Jon", and I have seen her maiden name recorded as JONSSON as well. They immigrated to Minnesota in 1912.
Don't know if you're still looking, but I hope this info is helpful!