Olargues is less than an hour from Beziers airport but there are plenty of other options, including:
Ryanair and Easyjet are the main operators for these airports and Ryanair flies to Languedoc from various UK airports. Scheduled airlines also fly to Montpellier.
Another option is the train. After the Eurostar from London to Paris or Lille it's only 5 hours on the speedy TGV to Montpellier or Beziers. Fast trains are also available from Barcelona and beyond. A great way to travel!
Car rental is available at all these airports and train stations. You could use public transport and taxis, but you'll see the best the area has to offer under your own steam.
If you prefer to drive, it's about 10 hours from northern France, so an overnight stop is recommended. It's also just over 2 hours from the Spanish border and the Pyrenees.