The nearest site to Carcassonne is
Camping Campeole de la Cite, which is just outside the walls of the old city. There are other sites in and around the area - we stayed at
Camping Le Martinet Rouge at Brousses le Villaret, 15 km north of Carcassonne - which we thought was lovely. Others have recommended
Domaine d'Arnauteille which is about the same distance to the south.
Our friend has a house nearby, and last year we passed
Camping Val d'Aleth, alongside the little river, smaller and in a typical southern village.
Then there's the
municipal sites, plenty of them all around and generally cheaper. The municipal site at Capestang, for instance *(smallish site, in a village alongside the Canal du Midi - where Terry Darlington sailed through). It doesn't have it's own website - but is VERY cheap - I think around 6 euros per night, from memory, when we had a look last year. You may find more information about campsites in the area, on the
Office du Tourisme website for that area. By the way, although the website showing the locations of municipal campsites has two symbols - tents and tents/caravans we've certainly seen caravans on some of the sites showing a tent only symbol.
In my opinion, whilst Carcassonne is lovely, and worth a visit, there are many other fantastic places in the area and you may actually be better a bit away from 'the madding crowds' in Carcassonne itself - just have a day and evening visit to the old Cite itself. Needless to say, it's an area we love, and keep going back to!