There are currently three legions stationed in Gallia Narbonensis. They are

Legio III Gallica [Narbo]
Legio V Alaudae (Larks) - taken from the distinctive crest that they wear on their helmets [Aquae Sextiae]
Legio XI [Valentia]


20 Sep, 2003 Update:
All three legions are deployed.
The Legio XI, up to this point unnamed, has earned the nickname 'Macteres', or 'Butchers', for their defeat of the Gauls at the Battle of the Plains.

A fourth legion, the first one to be raised in accordance with the Lex Valeria Provinciae Militaris, has been raised at Narbo. It's name will be the Legio IV Pantherae, or Panthers, named for their distinctive crests on their helmets.