A great secondary source for Norwegian family history research is Bygdebøker. Almost every municipality in Norway has published one or a series of books. Norway has had a large farming population, so by describing who lived or lives on the farms, most of its citizens will be included at least until 1900.
The authors of Bygdebøker uses an array of sources, often have knowledge of the local area and might get help from other knowledgeable family or local historians. One can find the local history going back 1-2000 years. If the farm was inhabited before, during and after the Black Death. And you might find lines of your ancestry going back to the 1600’s. It can name these ancestors born about 1600-1650. Give the names of their children and where they settled. From about the year 1700 it will probably list names of spouses, more accurate years of birth and death, and give more detailed information. This gives you the chance of connecting your research with that of others and helps you going to the primary sources with more ease. The modern Bygdebøker also includes other buildings and people than those on the farms.
Familysearch and the wiki is a great place for learning more about Norwegian genealogy. They say this about Farm books: “These books can be a real treasure for family historians, and others looking for their ancestors. A great portion of the Norwegian population does not live in big cities. They live in small towns and villages called “bygd”. The “bygdebøker” give us information about the people living on the farms in these communities, and a history of the communities.” You can read more here: https://www.familysearch.org/wiki/en/Norway_Farm_Books
Lokalhistoriewiki is a wiki written by volunteers and edited by employees in a division at the National Library, specialized in Local history. They have compiled bibliographies of the counties and municipalities in Norway in two categories: 1. Farm books and 2. Local history yearbooks and journals. The link is here: https://lokalhistoriewiki.no/wiki/Kategori:Lokalhistorisk_litteratur I believe this is the most comprehensive overview that can be found.
One of the most experienced Norwegian genealogists; Laila Normann Christiansen, has written a blogpost “An overview over Norwegian Farmbooks and their contents”, where you can find links to which Farm books contain village history and which contains genealogy / farm history. A link to the blogpost is here: http://www.lailanc.no/oversikt-over-norske-bygdeboker-og-hva-de-inneholder/
(Remember that the pages written in Norwegian can be translated. If you use Chrome, rightclick the page and choose “Translate” and appropriate language.)