Is there a problem for foreigners to registrate a car in LA?

I read somewhere that it's a problem for some foreigners (in this case Norwegians) to buy a car i LA. Or to be more precise, it's a problem for foreigners to register a car in their own name without a official US ID. To get one, it could take several weeks, and you had to be in US while waiting. And if I have understand it correctly, you must have your vehicle registreted in your own name while crossing borders in central america. Is this true? And how to overcome theese problems?