There are cheap tickets to India from USA, but if you are going nonstop, expect a long flight.
India Airlines has started to make non-stop flights from many American cities to 8 different cities in India. Flights from New York City to Mumbai, Delhi, Ahmedabad, Kolkata, Chennai, Bangalore, Cochin, Hyderabad or Trivandrum are only $399. These prices are exclusive of taxes and fees. The date’s available for travel is 10/01/09 till 10/30/09 and is open for week days only travel.
Air India also has flights to India from America and just like India Airlines the advertised price is enticing, but the $435 in taxes and fees take some of the glamour away. If you are going to travel to India, book well ahead and travel during the days of Tuesdays through Thursdays. The business travelers have many of the flights booked for Mondays and Fridays so avoid them if you are looking for a low cost deal. Likewise Saturday is generally filled by businessmen that either worked late on Friday or just wanted to stay one more night. Sunday is for the business travelers that are going to get off on Monday morning where they are going to conduct business.
Last minute standby and cancellations are a good source of low cost tickets, but they are not predictable and neither is the fare. For your best chance at cheap tickets to India from USA, book 2 to 3 months in advance. That is when you will find the best deal.