Here are a few links to bike and accessory shops, as well as some camping, clothing and book stores that we've used, says Lynette Eyb.
Bikes and accessories
For day-to-day stuff in France, we usually go to the local Decathlon, which is where we usually buy our kids' bikes. They are decent quality and sturdy. They also sell a full range of spares and accessories, plus have an atelier/workshop you can go to for repairs. Decathlon also delivers - it is possible to buy online in France and have your purchases delivered to your hotel. Many readers have done this for bike bags on one-way rides, or for bikes and panniers as it is sometimes cheaper to buy than to hire. See here for their bike bag.
Wiggle is a personal favourite and we use them quite a bit. They deliver to France (and dozens of other countries), and you can pay in your local currency. I use them regularly for their gift vouchers, which are great for cyclist friends.
Chain Reaction Cycles is among the largest online bike stores in the world – they have an enormous range and variety of bike stuff, from bikes and spares through to clothing. Free worldwide delivery with a minimum spend.
Halfords may lack the street cred of the stores mentioned above, but it's come on leaps and bounds in the last few years in both variety and quality, and scored a massive coup in securing the distribution of the Chris Boardman bikes.
Santa got a good deal on my Ortleib panners from SJS Cycles.
Books, maps and guidebooks
Stanfords is an excellent travel bookstore, with an amazing selection of cycling in France books and maps. They also have a great range of general travel guidebooks for France, as well as travel literature based in France. They also stock more than 4000 IGN maps. You can order online.
For French, Dutch and guidebooks in other languages, see this blog.
The Bike Ride Shop is a UK-based online shop specialising in cycling guides, books and maps.