Suppose you got a miss cal from number +9847XXXXXX, how will you trace the number at the moment ?, before going to cyber cell or on gov methods , there is a number of solutions.
Even if the exact tracing is bit difficult there are a number of ways we can reach the caller or at least his circle and provider . lets start with BSNL, whos is Transperant to a great extent
BSNL now got an online directory , with full features developed as a web application from where we can search any BSNL number for its address
Here is the link : http://www.bsnl.co.in/onlinedirectory.htm
Here we can select state then it will ask for District , it ll redirect to a screen for furtheer filtering, Almost everything is self explanatory here
from here we can reach any phone number with various search offered here
For rest Providers, this time i didnt have a link like BSNL directory, but pretty well you can trace the state and provider from this wiki page
Here First 4 digit code Provider and state is populated as units
Here the table means 9000 prefix is from
Provider : AT AIRTEL Bharti Airtel Ltd.
State : AP=Andhra Pradesh Telecom Circle.
Complete Abbreviations are on bottom of this page. if you are good with Excel and SQL , copy the text to excel and save it as .csv, port to SQL server with DTS wizard , and then can create any Web Application to fetch Number details
if you got any further websites plz share on comments