Directly to Rzeszów
By plane to Jasionka International Airport (RZE), which is about 8 km from the city centre. Flights are operated by LOT (with stop-over in Warsaw) or Lufthansa (with stop-over in Frankurft). More information on Wikitravel.
By plane to Warsaw
To Warsaw Chopin Airport by plane.
From Warsaw we advise to go by private bus (i.e. FlixbBus (reservation required, you have to go to Dworzec Autobusowy Metro Wilanowska) or Neobus - straight from the airport). It takes about 5 hours from Warsaw to Rzeszów.
By train from Kraków Airport
To Kraków Airport by plane and than by train from Airport (Kraków Balice) to Rzeszów Główny (with 1 change). It takes about 3 hours from Kraków to Rzeszów.