I've had a lot of questions surrounding the wherabouts of English books, even myself in my Master's program I haven't read a book in French just for the pure pleasure of it. English books are easier to read and tend to be more interesting to digest... many times it loses that flavor in translation-- no one wants a flavorless book.
Thus I've decided to discuss where to find English books, either to have for families with bilingual children or for those who simply love to read (like myself).
First off, the big stores:
Decitre next to Bellecour has a great section of Anglophone books, so much so sometimes I wonder why they even bother having French books. The issue is all the books are new, ie costly, and so we run the risk of spending lots of money for good reads. Anglophone books, like British goodies, are considered import commodities so they get away with charging even more than normal.
Looking for USED English books? Gilbert Joseph off La Rue des Marronniers offers a buy-back program for books as well as a section (third story, in the back) of used English books. It's also great for those who have a pile of English books and are ready for a change... can't guarantee that they will buy for a lot of cash, but in regards to changing it up... good deal. I was able to find a book sold at 10€ at Decitre for only 4€ at Gilbert Joseph. The pricing changes, as does the availability... it's sort of a hunt for what you want.
Amazon.com of course is another option for those not willing to scout for Anglohpone books- the best deal however is that in France books are FREE DELIVERY with Amazon. Not sure if it's a regulated country law or simply out of the graciousness of their hearts (have a hard time believing that one) but it remains a fact.
Fnac also has an Anglophone section, but their prices tend to fluctuate towards unaffordable. Hoewever if you have loads of cash and want a good ol' Anglophone library feel free!
For those with children in tow, or even French families looking to expand their bilingual repetoire- there is a fabulous Children's Bilingual bookstore in the 6ème, next to Rue Vendôme, called Inter Fun. Not only do they have English children's books but also German or Spanish for those looking to get that trilingual action in sooner than later.
Those are some resources that I've found. When in doubt scan the online ads for English books, I saw some listings at Little Britain recently that offered some great children's books for as little as 1€ a book!