MT Websites:
Montana Board of Oil and Gas
Montana Trust Land Mgmt

CO Websites:
Colorado State Land Board

IN Websites:
Indiana DNR Division of Oil and Gas

MI Websites:
Michigan DEQ, Office of Oil, Gas and Minerals

WY Websites:
Wyoming Oil and Gas Conservation Commission
Office of State Lands & Investments

TX Websites:
Railroad Commission of Texas

Federal Websites:
General Land Office Records