There are two international airports in Tuscany.
Amerigo Vespucci Airport (IATA code: FLR) is one of them. It is located approximately four kilometers away from Florence. Today the airport of Florence maintains direct connections with 6 Italian (Cagliari, Catania, Mailand-Malpensa, Olbia, Palermo, Rom-Fiumicino) and 18 foreign cities (Amsterdam, Barcelona, Brussels, Budapest, Copenhagen, Frankfurt on Main, Genève, Goteborg, London, Madrid, Munich, Oslo, Paris, Prague, Stuttgart, Vienne, Timisoara, Tirana).
It is very easy to get from the airport to Florence. Shuttle buses to the central station leave every 30 minutes (from 5:30 to 20:30) and every hour (from 20:30 to 5:30). Certainly, you can always take a taxi, but it will cost approximately 3-4 times as expensive.
Galileo Galilei (IATA code: PSA) is the other important airport, located 2 kilometers to the south from Pisa. It takes 10 minutes by taxi and 5 minutes by suburban train to get to downtown. The airport has a station of its own; and trains to Pisa depart every 20 minutes.