My best guess is that expat Capts will be needed here for at least the next 5-years. By that time they will have enough Indian Capt's trained. Contract companies do have contracts with individual carriers (aeropersonnel, contractair, parc, rishworth,directpersonnel, IASCO etc). In some cases you can apply directly to the airline. Some of the major players now in India are:
Spicejet-B737NG
JetAirways-B737NG, A-340, B777, ATR
Kingfisher-Airbus
Deccan-Airbus, ATR
Indigo-Airbus
Goair-Airbus
Paramount-Embraer 175
MDLR-Avro
AirIndia
Indian Airlines
Blue Dart
Alliance