The French Ministry for Foreign Affairs has put a tool on their website (in French, Engish, Spanish and German) which answers the question "Do I need a visa?" for many people. Go to http://www.diplomatie.fr, select your language and click on "Entering France". Indicate where you live, your nationality and the length and reason for your stay (the list of possibilites is extensive) to find out if the answer is yes or no. Simple, and straight from the horse's mouth.
My experience with the French consulate at home was terrible (in sharp contrast to the reception I received at the German one), and having this information without having to go through that experience would have eliminated a major source of stress.
Penny