Hi Manas,
I am not sure but try in this way..
First create a Organization.
Under that create Organization Objects ( Organization units, Positions ).
First Create Four Organization units under the organization.
1)NORTH 2) SOUTH 3) WEST 4) EAST
Under each Organization unit Create two more Org units
i.e for example as u mentioned For South 1) Chennai 2) Bangalore
For North 1) Delhi 2) Chandigarh
Under these Org units create Positions required and Create the Holder for each Position and assign the corresponding User master record for the holder.
Thanks and Regards,
DP.