What are good ways to travel across the country?

The usual methods ; car,plane,truck,motorcycle. Drive yourself thatz always part of the excitement of a trip. If you want to be on a bus for three of four or five days go for it.

Fly Frontier airlines or spirit to Chicago. Megabus has a hub there, and you can catch subways from each of Chicago's airports to Union station to catch the bus or a train.

You can fly: http://www.kayak.com/ . If cost is an issue, look into whether the budget airlines fly where you want to go:

http://www.southwest.com/

http://www.airtran.com/Home.aspx

http://www.spirit.com/Default.aspx

Short of driving yourself, the bus is likely to be the cheapest way to go if they have routes to your destination: http://www.greyhound.com/

Walk, run, drive. bicycle.