|Oh, the romance of the open road...|
Every airline has its own guidelines for extra baggage, including boxed-up bicycles. This article is a good starting point: Fly With Your Bike, but always check with your airline for the most up-to-date guidelines.
It just so happens that we are are one of the closest bike shops to PDX, as is evident on this map. We can disassemble and box up your bike for $40-$60, plus $10 for the box, and we can assemble and tune any boxed-up bike for $60-$100, depending on application.