Here are some tips for reading Norwegian parish records, which are the official vital records of that country from the 1600s into the late 1900s:
It is crucial to make sure you are reading the records of the correct parish, or you may pick up the wrong Gunder Gundersen or Maria Larsdatter. In Norway, one minister may have been assigned to serve 2 or more parishes, which formed a præstegjeld. Though each parish belonging to the præstegjeld had a physical church building within its boundaries, the life event records for all the parishes may have been recorded in chronological order in one book. In some areas, separate books for each parish were not kept until the mid to late 1800s. This can be helpful when doing Norwegian research, but, you still have to find out exactly which parish your person was living in when his/her life events took place.
Since the name of the farm or village your ancestor was living in was almost always recorded in the life event entry, you can determine the parish by looking up that little place name in a Norwegian gazetteer, which will give the parish name. For information on and links to Norwegian gazetteers, see the Norway Gazetteers article in the FamilySearch Research Wiki. To access free images of the Norwegian parish registers in the Wiki, see the Norway Church Records article in the Wiki.
Good luck with your Norwegian research! If you need further help, you can post questions on FamilySearch Forums.