Because directives require the enactment of national implementing legislation in the member countries, the EU researcher may also find it necessary to locate the national laws of other countries. Eur-Lex's National Transposition page allows one to track such implementing legislation.
The Foreign Law Guide (FLG) is, of course, another place to turn for such foreign (non US) legal research. The FLG also has an excellent, although somewhat dated, chapter on European Union.