Car Tax in Norway (Oslo)

Lets say I were to buy a car in Norway, god forbid. ontop of the purchase price what initial costs will I be hit with? regestration transfer?
Then, in the UK we have to get an MOT, Tax and insurance.... Lets forget the Insurance (not saying I will not get insurance but that will have no baring on the car I buy at this time) but road tax for the year? How much? MOT? How much roughly? Does the road tax have any significance to the engine size and can anyone tell me how much it is for diesel and petrol cars of different displacements? Also, do yuo get a reduction for getting an LPG system fitted?

Thanks

Rich