Given how easy it is to get a good quality used bike for a reasonable price here, I would imagine selling it would be the easiest thing to do. I'm not aware of shipping costs, though. These guys in Portland would be able to give you the best advice, I think:

http://www.citybikes.coop/index.htm

They put a lot of the good quality used bikes in Portland together, including my housemate's. They're a co-op, they're not interested in selling you something you don't need, and their collective knowledge pool of the area bike market is extensive.

If you want/need anymore Portland bike info/links, feel free to send me a PM. This is a great place to ride a bike.