[Butch Cassidy Slept Here]

I am sure Nortwest will appreciate my business

Don't be so sure. Northwest is, now, a wholly-owned subsidary of Delta Air Lines. There have been others on this board who have had less than favorable things to say about Delta. For domestic travel (within the "lower 48") I would use Southwest Air if at all possible. Renting a car, or using Amtrak (if available,) from your destination airport is preferable, in my view, to putting one's self at the mercy of most of the major US-based airlines. If travel on one of the "majors" is unavoidable I would recommend saving-up so you can afford to buy a fully-refundable ticket.