Dave, in Toulouse area, can I suggest you to visit the Aeroscopia museum:
http://musee-aeroscopia.fr/enAlso, if you're interested by modern stuff, you can visit the AIRBUS factories:
http://www.manatour.fr/en/aviation-tour ... sit-airbusAlso near Toulouse, you can also try to visit
http://www.replicair.fr/ - they are currently building 2 D.551's.
Near Bayonne, you've the helicopter museum at Dax:
http://www.museehelico-alat.com/ (the website is down).
Further in the north but not in your area, at Arcachon, you can find Bernard Chabbert and his Lockheed 12:
http://stearman-passion.blogspot.fr/Also in Bordeaux, the CAEA museum:
http://caea.info/index.php?lang=fr (sorry, I can't find the page in English).
I hope it helps a bit, thanks,
Ben