In this section the following words have the meanings indicated. “Custodian” has the meaning stated in § 4–101(d) of the General Provisions Article. “Public record” has the meaning stated in § 4–101(j) of the General Provisions Article. If the custodian of public records is not known and cannot be ascertained after a reasonable effort by a party in a legal proceeding, the party may request a court to issue a subpoena for the custodian of public records to be served on: A resident agent designated under § 1–1301 of the Local Government Article for service on a local entity; A resident agent designated under § 6–109 of the State Government Article for service on a State agency that is not represented by the Attorney General; or The Attorney General or an individual designated by the Attorney General as provided under the Maryland Rules for service on a State agency that is represented by the Attorney General. Service of a subpoena under this section is equivalent to personal service on a custodian of public records. The Court of Appeals may adopt rules to implement the provisions of this section.