Paris Gare d'Austerlitz
Most guests will arrive in France at CDG and need to transfer to Gare d'Austerlitz train station. The most reliable way to get from CDG to central Paris is by train, which runs every 15 minutes from 5h00 to 23h45 from terminal 2. You will find the train by following the 'Paris by train' signs with the 'RER' 'B' logos. Take the RER B to St-Michel/Notre-Dame, then transfer to RER C in the direction of Massy-Palaiseau/Dourdan/St-Marin-d'Étampes. Any train travelling in this direction will have Gare d'Austerlitz as the first stop.
Alternatively, you can transfer from the RER B to Metro line 5 (orange) at Gare du Nord, in the direction of Place d'Italie to Gare d'Austerlitz; this metro station is just next to the train station. The ticket you buy for the RER B train from CDG to Paris covers this transfer so no additional fare is necessary. Keep your ticket to use in the turnstiles as needed to make the transfer.
There are lockers to leave luggage (Consignes) at Gare d'Austerlitz train station. Note however that the station will give a rather messy impression as it is being renovated and extended; work is not scheduled to finish before 2020.
Paris has several main stations: 'Gare du Nord' serves destinations to the North, including Belgium, the Netherlands and the UK through hi-speed trains. 'Gare de l'Est' serves destinations to the east, 'Gare Saint-Lazare' serves Normandy, 'Gare Montparneasse' serves destinations including Brittany, whiles 'Gare de Lyon' serves the French Riviera, Switzerland and Italy.
Alternative TGV through Bordeaux route from Charles de Gaulle International
If you would like to avoid traveling inside Paris and dragging luggage around, but prefer not to take the plane. There is an alternative, from the Charles De Gaulle Airport train station (underneath terminal 2), you can take the TGV (High Speed train) to Bordeaux, and from Bordeaux change into a normal (regional) train to Terrasson. The total travel time will be about 7 hours.