There are various flights from USA to India.

They are broadly classified as

1. Airlines that fly over theAtlantic Ocean.
2. Airlines that fly overPacific Ocean.
3. Airlines that fly direct. Only a few airlines fly direct to Dehli andBombay

The way to find a cheap flight to India is to look at from where you are flying and the airlines that have the best deal to India.

The airlines that fly over Pacific Ocean are:

1. CathayPacific Airlines(CX):They have good price and connection from SFO and LAX and will halt in HKG. They are not the most kid friendly airline.
2. Jet Airways(9W): Jet Airways is known for its award winning customer service. They have partnered with United and Cathay Pacific up to HKG and then they take over the passenger to fly them to their destination inIndia. They fly to the most interior cities inIndiaand hence are a good choice for passengers whose final destination is not a gateway. They also have the cheapest fares.
3. Korean airline (KE): Korean Airlines is the best airline to fly to Bombay/Mumbai. They have the fastest time to Mumbai. The journey is so divided that they break inICN,Seoulwhich exactly at the mid of the journey. Hence your trip of 18 hours is divided into 9 – break for 2 hours – 9 and hence the most convenient. Their fares are also the cheapest in the market. The only drawback is that they do not fly everyday.
4. Asiana Airline (OZ): Asiana Airlines is forDelhiwhat Korean is for Mumbai. The journey is so divided that they break inICN,Seoulwhich exactly at the mid of the journey. Hence your trip of 18 hours is divided into 9 – break for 2 hours  – 9 and hence the most convenient. Their fares are also the cheapest in the market. The only drawback is that they do not fly everyday.
5. SingaporeAirlines (SQ): Singapore Airlines is one of the airline that take the longest to reachIndia. They have a long flight and a long halt at the mid points in the journey specifically inSingapore. On the positive side, they are the most kid friendly. They also fly to many southIndiacities and hence is a popular airline from SFO or LAX.

The airlines that fly overAtlantic Oceanare:

1. Lufthansa Airlines (LH): They have the shortest flight toIndia. Their hub cities,FrankfurtandMunichare well connected. The price to fly toIndiais pretty cheap but their change and refund penalty fees are high. They are not kid friendly as SQ is.
2. Emirates Airlines (EK): They have the shortes connection toIndia. Their hub cityDubaiis very popular for gold shopping before going toIndia. The food is excellent for Indians. The price of the ticket is not the cheapest and their change penalties are not the cheapest and they are not very kid friendly. Their network withinEuropeand middle east is excellent and they have very good prices for tickets which are multi destination with stops in Europe/middle east.