See the overview of customs offices at toll.no
If the foreign custom authorities have not already issued a transit document, Norwegian Customs will issue one. A transit document gives you permission to drive the foreign-registered vehicle from the Norwegian border to your local customs office (destination customs office). The relevant customs office will be stated on the transit document.
If the vehicle is insured, you will be able to use valid foreign number plates (registration plates) through to your local customs office.
If you wish to pay the value added tax upon crossing the border, you must check this directly with the border crossing office in advance.