Karl,
These people are freight "brokers"
http://www.freightcenter.com/
They'll sell your load to the best bid. You'll have to supply all the information, how many boxes, size, weight, etc.
I used them to ship a set of Magnum wings to the West coast. They email you all the forms to hand off to truck drivers and made it easy, as the shipping party.
Now all you have to do is convince the seller to do all the measuring, weighing, any packaging/crating and provide dock high loading or assistance to load.
Shipping an assembled boat on a car transport is another option, but it may be pricey. Reduced weight of your load doesn't matter because they could just as easily have an auto in that spot and they'll probably upcharge because they can't turn the key and drive your boat on the rack, and then there's the tie down issue.