The very first one that leaps to mind is The Talented Mr. Ripley by Patricia Highsmith. It's been eons since I've read it so I don't recall if it's as visually evocative as the movie was (can a book be "visually evocative"? Sure!) but it *is* set in Italy and it's a great read.

Another that leaps to mind -- and we seem to be following a movie theme here because this opens in theaters next week -- is Eat, Pray, Love. Only 1/3rd is set in Italy. And oh, it's not a novel -- it's a memoir. But still, very, very Italy.

Others that come to mind?

Hemingway's A Farewell to Arms was set in Italy. And was, well, it was great.

The Agony and the Ecstasy by Irving Stone

A Soldier of the Great War by Mark Helprin

Under The Tuscan Sun by... I forget who wrote it.

A Bell for Adano by John Hersey

And dare I say it? Angels & Demons by Dan Brown. (ugh!)

Frances Mayes wrote Under the Tuscan Sun. It was great movie, as well. I think Peter Mayle has written memoirs that take place in Italy. I know you were looking for novels, but maybe those will spark your interest anyway.

I liked E.M. Forster's A Room With a View (partly in Florence, Italy and partly in England.) I really liked the setting of Ian McEwan's The Comfort of Strangers (Venice) and I think he captured the claustrophobia of the city well but the story was very weird and offputting.

Tomato Rhapsody by Adam Schell (an old world foodie fable); A Good Year by Peter Mayle; Under the Tuscan Sun by Frances Mayes; a third of Eat, Pray, Love (the eating part) is set in Italy; Merchant of Venice;

Under the Tuscan sun best ever
bali

The Leopard by Giuseppe Tomasi di Lampedusa - An incredible novel set in Sicily during the late 19th Century.

The Law by Roger Vailland, set during a similar time in Southern Italy.

If you like mysteries, try Donna Leon. She sets them in Venice, and they're wonderful!

More mysteries, the Inspector Montalbano series by Andrea Camilleri, set in Sicily