For me, David Mitchell's Number9dream has been the leading contestant in this department for the last month.
Parts of Little, Big.
Annie Dillard's Pilgrim at Tinker Creek.
Some Angela Carter, Toni Morrison, Zadie Smith, Marisha Pessl, Bradbury, Guy Gavriel Kay and Elizabeth Hand.
Things these books have in common: a cinematic eye for detail, lyricism, a keen interest in playing with language.
Though I'm sure someone will, I'm hesitant to namecheck Lolita, and Nabokov's body of work at large, because while he is an incredible prose stylist, the effect is as often dampening (Nabokov makes me look like a dundering clodhead! why am I even trying!) as it is inspirational.