I'll let the Norway project people help you with sourcing, and who was related to whom, but I wanted to comment on Norwegian naming. Wayne is right, they didn't generally have first and last names, unless they were aristocratic or trades people, and then the extra names were associated with the aristocracy or the trade. "Iver Johansen" is not his name, "Iver" is his name. They only had a simple name that everyone used (and spelling didn't matter, it was only spoken), but when recorded or when meeting strangers, they would add additional names that indicated who their father was, and what was their town or farm. So typically, Iver's name could be recorded as "Iver Johansen Helland".
From that name, you KNOW that Iver's father is Johan, or a variation thereof like Johannes. If he grew up in Helland, then his father's name MUST be recorded as Johan something Helland, or variation thereof. If that Johannes Helland is not his actual father, then you're looking for another Johannes something Helland! That 'something' would be the name of Johan's father.
They also didn't have married names. If Anna was the daughter of Knut, another farmer on that same Helland farm, then the marriage would record her as "Anna Knutsdatter Helland", and that would not change after marriage. If she instead grew up on the Kleven farm, and moved in with Iver, her recorded name might change from "Anna Knutsdatter Kleven" to "Anna Knutsdatter Helland" (but her name is still just Anna).
We add last names now (and argue over them!), just to fit our modern ideas and genealogy programs.