I need to know any tips or tricks you can think of. I already use a host of web sites, I have flexible travel days and am looking at the "off" days of the week. The travel time is months from now. Anything I'm missing? Oh, car rental too. I don't have AAA, but I work for the government and have a costco membership.

Not all sources and strategies are best for all routes. What is your specific itinerary?

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Ok, coast-to-coast (USA?). If so, then what you're probably missing is the fact that airfare consolidators sometimes have very good coast-to-coast offers that you can't get other places. Not to push one site, but Cheaptickets.com seems to have this type fare more often than others. (Airfare consolidators are probably better-known for international airfares, especially in peak season).

The other thing you might be missing, if you're like most, is how to find the cheapest published fare on a route, and how to time your flight purchase. Farecompare.com is good to help you track them down, and it rates fares with stars (1 star = not so good, 4 starts= buy now!). It also shows a graph with fare history on the route, and lists the most recent fare alerts it sent when fare on this route dropped. Although it can not predict future sales, it does give you all the info you would need to make an informed decision. Good rule of thumb: 21-75 days advance for domestic flights.