Booking International Flights:
Kayak: http://www.kayak.com/
Momondo: http://www.momondo.com/
Skyscanner: http://www.skyscanner.com/

Small Budget Flight Companies By Region:
India: Spicejet: http://www.spicejet.com/
Asia: Air Asia: http://www.airasia.com/
Europe: RyanAir: http://www.ryanair.com/
US: VirginAmerica: https://www.virginamerica.com/
US: Southwest Airlines: http://www.southwest.com/

Budget Lodging Agencies:
Agoda:
Travelocity:
Priceline:
Hostelworld:
Booking.com:
Lonely Planet:
STA Travel:

Travel Advice/Agencies
TripAdvisor:
Trekkl:
Lonely Planet:

Silent Nature Retreats:

Awake in the Wild: