In today's world, a company's website is often the first point of contact. So a good website is essential for any commercial organization that wants to be taken seriously.
Here is a quick review of the big and small airlines in India. (I'm too lazy to type in the full addresses, but Google will quickly get you to any airline website).

The websites of Indian, Jet and Air Deccan do a good job of presenting information and facilitating booking-although Indian is a little behind the other two. They give a clear schedule of their entire network which is updated every day. Jet hasd a better online booking facility as you can book a multi-city trip (not just a return trip)

The "chhotus" like Kingfisher, Go, Spicejet and Paramount also have effective websites although I have not tried to book on them yet.

Many international airlines do not carry a full schedule (as it will occupy too much space) and thus have a provision for providing schedules only for the city pair you ask for. But since Air India and its Express are not having such big networks, they should be able to give their full schedules on their websites. Online booking seems to be limited to only some of the routes.

Sahara's website does not wish to let passengers know of their schedules. What are they trying to hide?

And Jagson, which has so much grandiose plans, has a fictitious schedule which shows flights which have stopped a few months (or more) ago. For example their schedule still shows several flights to Jaipur. But it does not even have a counter at Jaipur airport.

More comments are invited, especially on the online booking experience.