Buy your Paris airport transfer online

I picked up a les Cars Air France brochure in the shuttle bus on the way to the airport.
You can apparently purchase your Paris airport transfers online at www.aircityshuttle.com. When you arrive you’re supposed to take your voucher to the Air France coach service sales counter which is located between terminal 2E and 2F, exit 3, arrivals. This may be handy if you’re flying in on a morning flight and you know for sure that you’ll be landing at Terminal 2. Otherwise, I’d just wait until you arrive to purchase your ticket for several reasons. If you land in Terminal 1 you can pick up the shuttle at Terminal 1 Arrivals Level Exit 34. Also, if you arrive after 9:30 pm, the CDG-Montparnasse 4 line is no longer running. The CDG Arc de Triomphe line 2 runs until 11 pm. It costs 14 Euros one way to Montparnasse and 13 Euros to Arc de Triomphe. (Or 22 Euros and 20 Euros RT). This is by far the easiest and cheapest way to get into Paris. (the Montparnasse 4 line also stops at Gare de Lyon).