Michael Gilbert 
Etruscan Net [PDF ebook] 

Robert Broke runs a small gallery on the Via de Benci and is an authority on Etruscan terracotta. A man who keeps himself to himself, he is the last person to become mixed up in anything risky. But when two men arrive in Florence, Broke’s world turns upside down as he becomes involved in a ring of spies, the mafiosi and fraud involving Etruscan antiques. When he finds himself in prison on a charge of manslaughter, the net appears to be closing in rapidly, and Broke must fight for his innocence and his life.