#book a cheap flight
Last minute flight bookings – better to book online or at the airport?
I might contribute some inside knowledge since I am working for a company which contributed the software for a major cheap-flight company.
Generally the prices are determined by offer and the demand BUT there is another major variable (in fact several) in the game for short-booking. Statistics show that most (80%) last-minute bookers are in an important need for the short booking and therefore willing to pay more. So the function which generates the price for short-bookings is not a complete function of offer and demand any more like it was years ago.
If you want to know what’s the deal do the following: Go to your online bookers homepage. Search for a flight which is taking off today and try to book that ticket. With this you firstly know how short you can book online and secondly if the prices are acceptable for you.
Your question is also highly location dependant. In the country I live (Switzerland) I get the cheapest flights through a friend who works at the airport and calls me when a certain flight is available. I can only recommend trying both the online and physical approach.