Depending on how far you get - we've used Bois de Bardelet at Gien (Camping Cheques), the municipal at Coullons (just south of Gien on the N road), Camping Municipal at Nevers (Camping Cheques), Camping Chatel de'Neuvre at Chatel de'Neuvre, a site at St Pourcain (nice town for an overnight stop), La Grange Fort (Camping Cheques) at Parentignat just south of Clermont Ferrand, and the municipal at Issoire. I can recommend them all for an overnight stop. Some of the pitches at La Grange Fort have lovely views, and there's a take-away and restaurant there. Don't use the take-away at Bois de Bardelet unless you're desperate - we've had two really bad experiences there, but the site itself, and the restaurant, are fine! Camping Municipal at Nevers has lovely views across the river from all pitches, bit pitches, and a friendly 'small-site' feel to it - and there's a supermarket and fuel stop just down the road, easy access from the main road, too - but just a little tight actual entry into the site.
Haven't been to Valras Plage - but we've stayed near Agde at Serignan Plage, (OK but toilet blocks not as clean as they should have been, and a bit of a 'shanty-town' feel (doesn't take Camping Cheques any more), Camping Neptune (nice), Domaine de Champs Blanc (we like it, particularly the restaurant and the pool - but others have commented on the gravel pitches), looked at La Draggoniere but couldn't get a pitch, and at Le Boucanet near Grau du Roi which is further up the coast - but we love it there, directly on to the beach. (All these latter sites are Camping Cheque sites).