I sent one Fedex with clutch and stator, about $75. Can't remember the weight, somewhere around 100 lbs, definately under 150. Cooler is best, next is to build a crate out of plywood and bolt it to the crate and stuff the bejesus out of it with foam, etc.
Don't go UPS, heard horror stories of dropped motors.
Edit: if you want to weigh it, put it on a block on the bathroom scale, should be close enough. I weigh suitcases by holding them, then subtracting my weight, and I'm usually within a pound at the airport. Motors may be a bit heavy for that method.