Fedex, NW is going to probably be your cheapest way when going First or Business class. You could try American out of LAX, but I don't think they're as cheap as NW. JAL will only give you NW FF miles when you fly within Japan- anything flying into and out of Japan on JAL is NOT eliglble for NW miles.
By the way, if you've got a DH to Osaka sometime, try using NW to NRT, and then catch the ANA flight that leaves 2 hours later and goes to the Osaka Itami airport. It's a quick 25 minute, 600 yen bus ride directly from baggage claim to the Namba station. The bus leaves every 20 minutes from the airport.