Took our first and only domestic flight from Bagdogra (down the hill and about 12 km from NJP) to Delhi on Jet Airways.
The flight was comfortable enough and it included a short pitstop in Gwuaharti. Foreigners have to pay quite a bit more than Indians and must pay in USD for flights.
From Delhi, we arranged a car from the India Tourism desk at the airport to wisk us away immediately to Agra. We have a sunrise to catch at the Taj in the morning!!!