Vive la lecture!
From a young age, I have had a passion for reading and I am glad I am still a keen reader now. I read equally in French and English and have started reading in Spanish too. Really, nothing beats reading in the original version and it is a great way to develop your vocabulary and comprehension skills. I will recommend a few books I like on this page but I recommend you to go to the bookshops and libraries directly to browse and look for books that inspire you.
If you want to borrow French books, you can try the Barbican Library in Central London as they have a selection of books in foreign languages and the membership is free. The only thing is I think you will need to live or work in the City.
The French Intitute
Possibly the biggest pool of resources, books, DVDs and CDs in French in the French Institute 'Médiathèque'. There is a registration fee of £45 for a Classic Adult membership for a year but you can borrow up to 20 books, DVDs, Magazines, CDs for 3 weeks at a time.
The European Bookshop
One of the very first stop if you want to buy French books is the European Bookshop. They have a good selection of French books, premium or paper backs and also educational books for learning/teaching.
Waterstones Picadilly Circus and Gower Street
I am usually not keen on chains but the Waterstone Piccadilly Circus is a real book lover paradise with 8 floors dedicated to books and a foreign book department. I sometimes go to Waterstone Gower St too.
The foreign language department at Foyles, the massive bookshop on Charing Cross is good and you could have a look at their selection of French books if you are in the area.
My latest acquisition but it starts on a very dark note so not sure I will read it soon...
It got the famous French literary prize 'Prix Goncourt' in 2016 and the critics are positive.