This source provides context and definitions for key economics issues. For more comprehensive treatment select the Handbooks in Economics.
The first place to look for economics-related literature.
BASE - Bielefeld Academic Search Engine
Base is operated by Bielefeld University Library and focuses on academic sources including journals, institutional repositories, digital collections etc. with an emphasis on open access. BASE provides access to the full texts of 60% of the indexed documents for free.
Like Google, but for scholarly literature.
Academic Search Ultimate (EBSCOhost)
Comprehensive, scholarly, multi-disciplinary full-text database consisting of periodicals, including peer-reviewed journals.
Business Source Complete
Provides full- text for scholarly business journals and other sources. Coverage includes virtually all subject areas related to business.
For more, check out the main Economics Research Guide.