Many a time will is deposired at District Registrar office also. Will copies are not given to all until the death of the executor. If a person wants to have a copy of it then he must also produce a copy of certificate of Death.
As rightly pointed by someguy, it is very difficult to trace where it was registered. But there is a way. Apply an
RTI to Inspector General of Registration asking for the date and document number of Will if any Registered by --------- in all Sub Registrar and District Registrar of the sate.