I know about agrotourisimo's in Italy. Do they have something similar in France? I like to walk fields and talk to farmers about what they grow and the land they farm. I know, we all want to see the big sites. But, i also want to spend time with the grass roots people. I had an experience with a farmer in Germany nearly 20 years ago. We kept in touch for several years before he passed away. It made the trip one of the most rewarding experiences of my life.
Try Gites de France - they have a selection of farmstays, it's called 'welcome to the farm'.
http://en.gites-de-france.com/holiday-rentals-Welcome-to-the-farm.html
I've toured throughout France north of Paris and from Paris to Switzerland. The farms in those areas are very large and very modern by U.S. farm standards.
On the other hand, the farms in Tuscany are very small but productive. Agriturismo apartments and rooms are also on virtually every farm outside of Florence.
I worked for one of the large tractor and equipment companies, and France is a very good market for large tractors. Agriculture and equipment manufacturing is a truly worldwide business.
vaughn-this is not quite what you're asking for, and you may be aware of it already, but I've known several people who have done WWOOF-ing as a way to connect with ag in places they would like to travel to.
In general it's a program where you commit to work for a time on a farm, without compensation other than room and board.
Here's a link to the WWOOF France site:
http://www.wwoof.fr/
And to the Worldwide site:
http://www.wwoof.net/
David is correct for the north of France where the farms are indeed giant companies, but from the middle of Burgundy on south, in Brittany, and in Normandy, there are still many small, family-run farms. The EU is trying to consolidate farms, and what type of farming is in what area of the EU, but tradition is surviving.
Nancy has a good lead for farm stays with the gites de France.
We stayed at a 300 year old family farm near Bayeux. Check out www.bandbnormandie.com. Odile, Jacques, and their two sons will welcome you with open arms. Rooms were modern, Odile's breakfasts were to die for and they told us where they go to eat and shop in nearby small towns, the closest being Villers-Bocage, about 15 miles east of Bayeux. They know all the farm families nearby and can probably get you onto most of them. We took a train from Paris to Caen and picked up our car there. It's an easy drive, maybe 40 miles to La Ferme du Pressoir.