@prateek007391 : Congratulations On successfully configuring your phone
By default there is no need to have a data plan for BSNL 3G, all mobiles will be charged at 1 ps /10KB thats Re.1 / MB.
Though I dont have a dedicated 3G dataplan , the CC told me to top up with any of the plan in the following link.
:: BSNL 3G ::
You can go for 606 plan which gives you 2GB + 5GB night free (11 PM - 7 AM) for 30 Days.
a Rs. 222 recharge will get you 500 MB for 30 days.
You need to do a easy recharge on that , recharge cards are not available. Please get this clarified from your local BSNL CC.