Online Economics Encyclopedias, Dictionaries, & Handbooks
Encyclopedia of Business and Finance 
Covers accounting, economics, finance, information systems, law, management, and marketing.
Encyclopedia of Global Change Covers such topics as environmental economics, ecotaxation, the commons, land use, sustainable development, valuation, etc.
Oxford Encyclopedia of Economic History Provides lengthy articles on economic history. The print edition of this set runs 5 volumes.
Worldmark Encyclopedia of National Economies Covers the current and historical economic development of almost 200 nations.