FNAC.com
To book tickets online, just click on the section marked "Spectacles".
http://www.fnac.com/

L'Agence de Theatres de Paris
Book seats to shows, concerts, operas, ballets and more.
http://www.agencedetheatresdeparis.fr/

Le Kiosque Theatre
Le Kiosk Theatre sell cut-price tickets, on the day, to theatre shows and musical events, from two outlets in Paris.
http://www.kiosquetheatre.com/

Ticket Clic
Purchase tickets instantly via the Web.
http://www.ticketclic.fr/

Ticketnet
Buy tickets online to shows, concerts and sporting events.
http://www.ticketnet.fr/