My favorite place to start the flight search is hipmunk.com. It gives you a view of who goes where and for what price. Then I typically buy from the airlines website (unless the prices are less on hipmunk, which proved to be true in Thailand for some reason).

I don't bother with the Southwest $12.50 Express Checkin.

Here's how Southwest works. They don't have any assigned seats but rather open seating based on groups A, B, or C, and #'s 1-60 (or so) within each group.

When you check-in you are assigned a Letter-#, A-1 to A60, B1-60, C1-60.

If you checkin online exactly 24hrs before departure you will get a # ranging from about A40 through mid B's, then if you show just show up at the airport then you can get a later boarding #. You will be get on the plane, and your seat will take off and land at the same time as the others. C seats are usually all middle seats in the 3-3 seating, and overhead storage space may be harder to find.

If you do the Express checkin you usually get a group A, which means you are guaranteed an aisle or window seat, and a seat more forward in the plane if you want.

So if you don't care where you sit, checkin online at your convenience - Southwest has a good smartphone app.

Worst case you just checkin when you get to the airport.

^bardo1 - I travel with a khe sera sera attitude - this makes the whole experience an adventure so "bearable" is definately in my vocabulary :) Thanks