In reply to Woodsy75:
HA! Just sent you an email as I too am a new user and wasn't able to reply to this until just now!
I basically said...there are plenty of small huts (lots of them look like old Anderson shelters) that you can just turn up to. They're unattended, just marked on the map as a refuge, so you can turn up whenever- as long as they're not already full. Not much way of telling what they'll be like until you turn up. I've seen some that can take about 10 people, water trough outside, maybe a picnic table...ranging to tiny little huts that time seems to have forgotten.
As mentioned, you can book for the bigger ones, and it's probably wise to do if you're going at a busy time of year. They're run by the club alpine Francais.
http://www.ffcam.fr/
Happy adventuring!