I bought a few books from flipkart.com. They have a wide range of books. The selection is quite impressive, but the prices are more expensive than other sites like landmarkonthenet or infibeam.
The speed of delivery is unmatched if the product is in stock. They deliver in 2-3 days if the product is in stock. I was trying to order "Moby Dick: The whale" from them, but the estimated delivery time was 12 days from the date of order. Obviously, the item was out of stock and so I had to order it from infibeam. Infibeam took around 5 working days to deliver it.
I noticed two things about shopping online for books :
If you order by credit card, the courier will not be able to find your house and ask you to pick it up from the courier office.
If you order by cash on delivery, the courier boy will be able to find your house without any trouble at all. Plus the courier boy will be extremely courteous.
I found the above to be true regardless of the website chosen. Human nature I guess.
You get a separate proper invoice when you order from flipkart. With landmark you have to tear out the invoice from the packing materiel with some effort.
Flipkart requires a minimum order of Rs 200 to qualify for free shipping. Other sites do not have this rule.
Finally, flipkart books are certainly more expensive than infibeam or landmarkonthenet sites. Most of the classic books that I have bought are generally Indian imprints by reputed publishers. They were priced higher on flipkart for some reason. I guess someone has to pay for all those cute ads on television.