Facile à dire!
This thread at Wordreference French forum gives links to dictionaries, sites that can help with verb conjugations, and sites for general help with French grammar.
A French thesaurus.
Lexilogos has links to numerous French (monolingual) dictionaries, including dictionaries of Old French and French language from the 16th-20th centuries.
Vis-à-vis Online Learning Center: www.mhhe.com/visavis5
Embassy of France in Washington: http://www.info-france-usa.org/
Le Devoir: http://www.ledevoir.com/
Le Monde: http://www.lemonde.fr/