Buying detailed maps in France

IMHO your best bet is to get some sort of gps such as Garmin. The road maps will get you from town to town but once you get to some of those small towns the gps is invaluable in terms of time and frayed nerves. I would suggest buying one before you leave and familiarize yourself with it. The cost of renting one from the auto rental company over a two week period will run you about the same.

Most service stations will sell the Michelin map books, which are just about the most detailed you can buy.

I recommend both of the above -- a GPS and a good map to supplement it. GPS is very good but when it's wrong it can really mess you up if you don't have the paper reality check a map provides. We bought a Michelin road atlas of France in a Paris bookstore and I saw them at the autoroute rest areas and elsewhere. Very thorough and also very heavy in our luggage coming home.

I concur with Dick re: a good map book and yes they are heavy. I would add a good dose of common sense when the gps wants to send you down a cow path as the shortest route from a to b.

The gas stations on the toll roads have them.
If you want a Paris street map you can buy one at any newsstand. Make sure to get the blue book "Paris par arrondissement - L'indispendable".
All the streets in Paris are listed.

I like to plan out my route the night before, so need a good map. IMHO, GPS is not a good substitution for a map, which will give you an idea of the lay of the land as well as what other interesting sights might be on your route. However, GPS is useful in towns and cities and for helping to find out-of-the way B&Bs.

I use a combination of GPS and maps. For going a long distance, I like to have an idea of how I'm going to get there ahead of time, and then use the GPS for major navigation. For local, more rural towns, I prefer the IGN maps to the Michelin. They're harder to find here, but I order them direct before my trip. http://www.ign.fr/ or http://www.mapsworldwide.com/ign-blue-series-maps-index.asp. I particularly like the blue series maps (1:25,000) when I am in an area of a few towns and want to find my way through the area, including the back roads.

I have seen them in most of the larger stations on the toll roads and in book shops in towns.
you will find with the Michelin roads maps ( great BTW) are available in two different scales. the yellow coloured are typically 1:150,000, which are very detailed and good if you are touring a small area ( or buy a few- they usually cost about 7euro etc) OR the orange coloured which are larger scale typically 1:400,000, which show a much larger area, but with less detail, eg: no small roads. and cost the same.
Believe it or not I buy mine on-line ( all the way from the UK- much cheaper) before we go, to help our planning, then we have them ready to go when we are there. then we highlight the route we end up taking, as a memory of our holiday. packed in the bottom of your suitcase they don't weigh much.
Even with a GPS I would not be without the maps, if only to identify tourist spots to look at along the way, something the gps doesn't do.

hope this helps.

We found maps easy to find -- at bookstores, even at small "tabacs" (little neighborhood stores).

We've bought a Michelin Atlas (basically a spiral-bound book of maps that cover all of France) in small "everything" stores I'm sure a bookstore would have them, too. Yes, they are bulky, which is why we buy them in France. We have found the Atlas to be very helpful, for reasons cited by others here.

I bought the more detailed Michelin maps in Paris before a trip to Burgundy and Alsace. Thankfully my rental car had built-in GPS or I never would have found anything in Burgundy. First off, the maps are huge because there are so many back roads. An atlas sounds like a much better choice. Second, a lot of those back roads are not well-signed. Too many intersections either didn't have signs for all the 2-4 roads that intersected, or worse, all the names were on one signpost with arrows and the signpost was askew, so you couldn't tell which was which.

Bookstores all over France generally have a good selection of individual Michelin maps, which is what I've always relied on.

I suggest the yellow Michelin road maps, very detailed, France divided up by square or rectangular region, Provence, Alsace et Lorraine, Normandie, Bretagne, etc

We bought a small sized atlas at the airport on arrival and brought our GPS from home with all lodging and some of the tourist sights programmed in.

We hardly used the atlas which surprised me as we had used one frequently in Ireland.

If you program the GPS to take the fastest route you will indeed be directed down cow paths and through tiny villages. When we decided to follow road signs instead it would be via larger roads but actually wasn't as fast.

Cow paths and tiny villages are part of the charm of the journey after all :D