I have been looking for local festivals and (food??) fairs in Provence, Champagne, Alsace Lorraine, Rhone Alpes and the Loire Valley in May and June. I have looked up a lot of websites, and have found the Cannes Film Festival and a few other bits and bobs but really looking for true local events rather than international galas. Any ideas?
You can look for B&B´s in the region you plan to visit and ask about local festivals and other events. And ofcourse contact the local Tourist Offices. Gîtes de France is the largest organisation for B&B´s in France: http://en.gites-de-france.com/
while staying in Saint Remy, in june, we had a delightful day at the market in nearby L'Isle-sur-la-Sorgue, possibly not what you are looking for ? but I am sure there are many others if you contact the local tourism offices etc.
Here's something I found by Googling "special events Provence 2016": http://theprovencepost.blogspot.com/p/events-calendar-this-list-updated-often.html
There were a bunch of other hits. Looks like quite a job to go through them all, though.
Most towns have a regular weekly farmers market which is wonderful to see. Just google farmers markets in provence and you will find the weekly schedules. To see the markets is great, but also to avoid the market day in the smaller villages is a good idea if you really just want to see the town. sue