You can pre-order Lumia 510 for Rs. 9999, As Nokia itself has said that they will launch this phone under Rs 11000 and they had kept their words. Currently phone is out of stock on flipkart but they will add it soon.
If you don’t know about Lumia 510 the it’s a 4 inch display screen phone with screen resolution of 800×480 pixels, has 256 MB RAM, 800 MHz single core processor, 5 MP rear camera, no front one, 4 GB internal memory no memory card slot, 1300 mAh battery.
You will get 7 Gb of free SkyDrivecloud space and like all other WP7 devices this one too get WP 7.8 update soon.