Once again, Scott McCartney (WSJ’s The Middle Seat) comes through with some salient tips about  buying airline tickets, while debunking some popular myths.  In a nutshell:

1. Non-stop flights are generally less expensive than flights with stops — especially in markets with low-cost competition.  Non-stops will most likely cost more on international flights and cities serviced by fewer carriers.
2. Sunday is still the best day to buy tickets, with Tuesday the second best.  Avoid Wednesdays and Thursdays if possible.  Ironically, Tuesdays and Wednesdays are the least expensive days to travel because “who wants to travel on a Tuesday or Wednesday?”
3. Include a Saturday overnight stay to get the best discounts on international fares.  Domestic is a different story, although it still may help lessen the cost.
4. Supply and demand is what drives pricing now.  The tie-in to oil prices is no longer relevant.  So fuel costs might go down and fares will still go up due to lack of available seats.
5. According to a study by Expedia/ARC, the best window for buying tickets is three months before departure —  up to three weeks before.  Once inside 30 days, travelers are at the mercy of the airlines.