by car: Driving is not the easiest way to get to Paris or to travel within the city (and it isn't very pleasant either). Parking space is very limited. If you wish to come by car nevertheless, make sure that your hotel provides a parking area. Note that there is no parking available at the meeting venue.
Local Transport
by metro/bus/RER: You can download a guide to the public transportation system including a map of the metro lines here. If you plan to use public transportation frequently during your stay, you can buy a 'Paris Visite' ticket which grants you unlimited access to almost all transportation systems for up to 5 days.
by taxi: The common telephone number for all taxi companies is 01 45 30 30 30.
by bike: You can find 'velib' bike-sharing stations everywhere in Paris.
Tourist Information
The website of Saint-Germain-des-Prés (the quarter around the meeting venue).