This question has come up a few times over the years. Here's some of the results I found when doing a search:

Importing BMW X5 35D from US to Switzerland

Buy new car in US or buy local?

Auto Insurance on imported car...

Car import - where and how do they know about 6 month ownership?

[Import] Bring car to Switzerland?

Volvo S60 import from USA

How I imported my car from the UK (yes, it is about a UK car, but it will give you some ideas...US cars are a bit different, but you'll see that in other threads)

Importing car from US to Switzerland - anyone has Honda Pilot?

Fees/taxes about car import from US

car import from USA

Car imports: what did you have to change?

Importing Car from US

Buying new car from US? (now that $=Franc)