The nearest airport is Willard Airport (Champaign), airport code CMI. American, Delta and Northwest Airlines all have service to Willard Airport.
The Champaign-Urbana Mass Transit District has regular bus service from the airport to the Illini Union. Hendrick House and the Hampton Inn are both within walking distance of the Illini Union. Schedule of the CUMTD AirBus.
The Illini Limo (217-384-5892) meets most flights, and transports to all local hotels. They have a small stand next to the baggage claim; check in with them after landing. The fare is $13 one way to any location on campus.
It is also possible to fly to Chicago's O'Hare Airport and take the Lincolnland Express shuttle to the UIUC campus. The shuttle takes about three hours (one way) and costs approximately $50. Upon arrival in Champaign-Urbana, the shuttle stops at the Illinois Bus/Train Terminal and at the Illini Union.