Airfare - when to shop?

[classicpooh]

We are going from Chicago to Orlandoo in August - when is the best time to start shopping for airfare? Anyone have carrier suggestions?

[TravelSheryl]

Once Southwest airlines begins selling your travel dates, because in all likelihood, you will not get the best fare before that time (unless you fly Spirit Airlines) on any airline. Southwest will probably be selling August travel within the next month to 6 weeks.