EUR-Lex - Access to European Union Law
Fulltext European Union / European Community legislation, case law, and preparatory documents. Includes treaties between EU member states, international agreements, secondary legislation, and supplementary legislation, decisions of Community law courts and opinions of the Court of Justice of the EC and opinions of the Advocates-General, and parliamentary questions.
Eurostat - Official database for EU statistics
Europa - Primary European Union Web portal
Archive of European Integration - University of Pittsburgh archive
EDRIS - Humanitarian Aid Reports
ECLAS - the European Commission Library Catalogue. Available in French and English. Includes the complete database of 350,000+ records and links to many documents online.
Also, consider using the following more generalized databases to get started with research on the EU:
JSTOR - Specializes in making available the back issues of journals in a wide variety of humanities and social science disciplines. (After clicking the link, you'll need to sign in with your PennKey and password for University JSTOR access.)
EBSCO MegaFILE - General, multidisciplinary periodical database, covering all scholarly disciplines, with many general and popular magazines, and news sources.
Historical Abstracts - Historical coverage of the world from 1450 to the present.
PAIS International - Contemporary public affairs and policy issues worldwide related to a wide range of topics: agriculture, banking, finance, business, demographics, education, health, environment, planning, public administration, law and legislation, and international relations.
European Integration Online Papers - The only peer-reviewed E-journal in the field of European integration, published by the European Community Studies Association (ECSA), Austria since 1997; authors retain their own copyright, and the journal is freely accessible on the Internet.
Archive of European Integration (AEI) - Since February 2003, an "online repository and archive for research materials on the topic of European integration," freely accessible on the Internet, containing full-text copies of independently-produced materials such as working and policy papers and journal articles, as well as some official EU documents - primarily historic documents that are difficult to locate or not online elsewhere.
CVCE: European Navigator - Contains over 16 000 documents on the European integration process. The key post-war historical events and the European organisations are presented chronologically and thematically, and are illustrated by a wide range of archive documents, as well as interviews conducted by the CVCE with people who have been actively involved in European integration.