I shipped my wife's minivan with
http://kellysautotransport.com/?page_id=10 for a trip from Norfolk to North Island and then two years later from North Island to Newport RI. I was really happy with both moves.
They were able to provide a 3 day window vice 7-10 days that some of the cheaper companies wanted.
Things you want to know:
What is the pick-up window (number of days).
What is the expected delivery time. This can vary since they may be dropping cars off in East Bumf*ck before dropping your car off.
Will it be an open carrier or closed. (Closed is more expensive. We talked to the driver about putting our car in the middle of the rack and never saw a ding from either move)
Will they come to you to pick up or do you have to go to a central facility. (Could be an hour or so away)
How much stuff can you have in the car (usually less than 1/4 tank and under 100 lbs).
Will they deliver to a specific location or do they drop off at a central facility.
Can someone other than the car owner sign at pickup or drop off, if so, what documentation do they require.
I made sure I tipped the driver about $30 so he could get a couple of meals while moving my car. Don't know if it made a difference or not, but both times, I've been very happy with the result.