UN/OLA/DOALOS : The United Nations Division for Ocean Affairs and the Law of the Sea 

ISA : The International Seabed Authority

CLCS: Commission on the Limits of the Continental Shelf

CMI: Comité Maritime Internationale

ECOLEX: Data base for legislation

ITLOS: International Tribunal for the Law of the Sea

UN: United Nations

UN INTERNATIONAL LAW: International Law at the UNited Nations

United Nations Treaty Collection On-line: Collection which includes a large number of categories and treaty-related data

Maritime Space: Maritime Zones and Maritime Delimitation (State Practice on the internet) 

My EEZ, the Exclusive Economic Zone Community Site

Limits in the Sea (US Departement of State Database)