There are a very few options for one to buy books online in India – and suprisingly, book prices vary enormously across different websites (also a function of your delivery delay).
Iglooo, a Pune based startup has launched a comparison service that enables you to search for a book title/author and compare the same across the online book stores (currently, they source data from Landmarkonthenet, A1Books.co.in, First and Second).
The interface is neatly laid out (focused/no nonsense approach) and one can search by title/author.

I did a quick comparison with Flipkart and have mixed results – a few books are priced on the lower side (Igloo will monetize using referrals).
Do give Igloo a spin and share your comments.