Don't expect it to be cheap at all! We recently (within the last year) purchased a car from California and had it shipped to Wisconsin. Thankfully, I work in a Distribution Center and we also have a building in SoCal where the car was. I had it shipped on a company truck, and still ended up paying like $650. The cheapest quotes we received were around $1100.
Do a google search on like "car freight" and you will get a bunch of companies. I would stick with a larger company (American Freight, Yellow, Conway Central Express, Dawes, etc).
Good luck! From my experience, it's probably not worth it (my opinion)
what kind of car is it that they want it so badly to be shipped to CA? We shipped ours in to have a rust free car (cuz it's a 92).
They aren't paying with a cashier's check for a couple grand over the asking price and you wiring them the difference, are they?