Shipping a JDM (Japanese Domestic Market) car to California isn't impossible or even difficult--it's just incredibly expensive and time-consuming. Japan and America have different crash and emissions test standards, which can make registering a JDM car in America a tricky proposition requiring tons of legal paperwork and expensive modifications. California is particularly strict when it comes to registering foreign cars, but it's something you'll have to endure to fill that yen for an R34 Skyline or JDM Civic Type R.
Check the National Highway Transit and Safety Association list for vehicles eligible for registration in California. The list of eligible vehicles will include a sub-list of modifications required to make the car meet U.S. crash-test and emissions requirements. Right-hand drive is often a deal-breaker for importation, but you'll be able to certify the car if any version of it was ever offered in left-hand drive.
Locate an NHTSA Certified Commercial Importer or Independent commercial Importer. Famed importer Motorex is now out of business, so take a look at the EPA list of certified importers in the resources section below. That list is current as of 2009, but the difficulty of car importation should be evident by the fact that there are only seven certified importers in the country.
Pay to have the car modified to meet U.S. requirements. For example, modifications required to register a Nissan skyline include new front and rear shatter-proof glass, new bumper supports, stronger inner door supports, U.S.-legal headlights and tail lights and U.S.-spec catalytic converters. Each importer has their own set of standards, which are approved by the EPA and NHTSA; not every importer can import every vehicle, so you'll need to shop around.
Fill out the appropriate paperwork. Your importer should walk you through the appropriate paperwork, which will include an NHTSA and EPA certification, VIN registration, importer registration and certificate of modification and inspection. After you get the paperwork filled out, the procedures for registering the car are the same as they would be to register a car from out of state.
