You should definitely book on-line through the airline's website. Bonus miles aside (like 2,000 on NW now) you get what you want quickly. Whenever I attend a meeting with my airfare paid by someone else, their travel agent never books me on the airline (much less flights) I want, even though I write it all down on my travel registration. Check out www.itn.net or www.expedia.com free for overall prices and schedules, then book your travel on the airline's site to get your bonus miles in the finest tradition of a "webflyer".