They have good amalgamations of the new books coming out each month.
In addition, Amazon.
Amazon certainly is one that I consult, along with The New Yorker. Also read blogs like Conversational Reading and Three Percent, which cover translated fictions better than any other site I've come across.
All have good to relatively good book reviews as well for history/non-fiction. So does Spiegel.
The New Yorker and Harper's are two others that I like as well, along with the sites I mentioned earlier.
Je suis méchant.