Hi Naresh Get in touch with any Prometric testing center. They will give you the exam voucher. It costs aroun $150 which is around Rs.7200/-.
Sun had recently declared a scheme of 20% discount for those who purchase the vouchers before 31st July. I registered before 31st July and paid around Rs.5800/-. I don't know if the scheme is still valid.
The best center would be NIIT CATS at Safdarjung Development Area.