V.T.
Southwest and I believe Air Tran will refund you the difference in their ticket prices in the form of a credit if the ticket price goes down before you fly. However, you have to be the one to find the difference, they just won't do it. I know Virgin America only goes to limited places out of DFW, but they had some really great rates, and it was the best flying experience that I've had. Usually though, I end up finding the best rates on American. I don't use travel websites because they are usually the same price as the airlines and they charge a fee. A friend of mine just used travelocity over the summer and when they changed their flight, travelocity never changed it with the airlines so they had to cancel their trip because the cost of the ticket was over double of what they originally booked for.