The options are:
-box it up in a cardboard box and take it on the plane.
This is probably the cheapest option, but may be logistically challenging and time consuming. The box can be acquired at a bike shop, usually just by asking for one. Lonely Planet bike guidebooks have some pretty good packing instructions. The airline will charge you $50-100, depending on the airline (frontier & southwest are cheapest). Getting the box and packing it can be a hassle, esp. if it's the first time you have done it, plan to spend a couple of hours packing, and think about how you are going to be able to get where you need to go with your now very-difficult-to-move boxed bike and pile of panniers. You can box it at your hotel/campground and then take a shuttle or taxi to the airport. Or you can pay a bike shop to do it for you, and take the bike on the plane. You *might* be able to get a box from the airline and box at the airport, and this would be the least annoying, but you need to confirm box availability beforehand (not on line, by talking to a live person at the airport) and leave plenty of time to do it. The airline boxes are usually huge, though, so it's really easy to get the bike in.
This all also applies to the bus or train.
- have a bike shop pack & ship it for you. Shop will charge you (don't know how much) for service & shipping.
-pack and UPS/Fed Ex it yourself - this used to be economical, but has become expensive.
good luck and enjoy your trip!