Two sources for E.U. information stand out in my mind. First, the European Union's Europa, which posts (a) EU news and press releases, (b) links to EU Web sites, including the European Parliament, banks, courts and agencies and (c) the best collection of EU legal materials on the Web, via the EUR-Lex portal.
Second, an excellent source of material and information is The Delegation of the Commission of the European Communities (212-371-3804). The Delegation's mission is to provide information on EC/EU policies.
Also, the Library Information Services of the E.C. info line can be a good information source (202-862-9539).
For an overview of EU resources, see European Union Law: An Integrated Guide to Electronic and Print Research by Marylin J. Raisch, European Union Legal Materials: An Infrequent User's Guide by Duncan E. Alford and/or the "European Union Resources" chapter of Legal Research Methods in a Modern World: A Coursebook (DJØF Publishing).
Following are sources I've found for specific materials:
Legislation & regulations: Several publishers have put out useful selections of E.U. law in English, notably, Oceana's European Union Law Guide, Sweet & Maxwell's EU Karnov: Deskbook of European Union Laws, CCH's European Union Law Reporter.
Europa's EU Legislation section provides access to most significant EU legislation including (a) all EU laws in force (EUR-LEX), (b) the Official Journal of the European Community, which is where the EU publishes its session law, new regulations, etc., (c) summaries of EU laws, (d) an index of "Community Legislation in Force," which tells you where to look in the Journal for laws on a particular subject (e) "Consolidated Texts," which is similar to a codification in that the original text of EU laws in force are presented as amended by subsequent legislation and more, (f) national legislation, (g) proposed legislation.
Additional materials may be available on Lexis and/or Westlaw.
Judicial Branch: The Court of Justice of the European Communities is an appellate panel responsible for interpreting European Union law and treaties. The Court of Justice is assisted by a Court of First Instance and a Civil Service Tribunal. The official case reporter is called European Community Cases. Other reporters include the Common Market Law Reports, CCH's European Community Cases and CCH's Common Market Reporter.
Court rules, contact information and additionl information is available on the Court web site. The Court's judicial opinions are available from:
(a) The Court web site, which has Court of Justice opinions from 1954, Court of First Instance opinions from 1989 and the Civil Service Tribunal from 2005. The case law of all three courts is searchable from 1997, including materials not in the official case reporter. The site also provides a topical case digest, a subject index and annotations;
(b) The "EU Case Law" section of Europa's EU Legislation page;
(c) Lexis (EUROPE;ECLAW);
(d) Westlaw (EU-CS-ALL);
(e) Caselex, which provides "the most important national and European case law linked to the EU's commercial areas of law;"
(f) The Delegation of the Commission of the European Communities (212-371-3804);
(g) Libraries holding the relevant case reporters, including the Fordham, NYU and Columbia law school libraries.
Treaties: The Treaty on European Union, the Consolidated EC Treaty, the Treaty of Amsterdam and many Intellectual Property conventions are published in volume 4 of the CCH Eadditionaluropean Union Law Reporter. The Treaty of Rome and the Maastricht Treaty are posted on the Internet by The Multilaterals Project. Many other EU/EC treaties are posted in the "Treaties" section of Europa's EU Legislation page.
Otherwise, call the Delegation of the Commission of the European Communities (212-371-3804) or see the sources listed under the separate entry for "Treaties - Foreign."
Other materials: The EU's Publications Office lets you search for and order EU & EC publications. CLEX on Westlaw offers EU National Provisions back to 1989 and preparatory documents of the Economic & Social Committee, Court of Auditors, European Parliament and European Commission. COM Documents and Presidency Conclusions of the European Counsel are posted by the European Parliament.
All official EU documents since 1952 are supposed to be available free through a "Digital Library" accessed through the EU Bookshop Advanced Search. Scroll to the bottom of the Advanced Search page to see a mention of the Digital Library.
The EU posts an on-line catalog of EU materials on ECLAS. If you have a subscription, the Foreign Law Guide (formerly by Reynolds and Flores) discusses the EU's primary legal materials and lists the treatises available in various subject areas.