The Savage Garden by Mark Mills
I picked this up at Waterstone's in Edinburgh as part of a "Buy 2, get the 3rd free" deal (as excited as I was to finally be in a bookstore with books in English I was also very aware of the pound/dollar conversion rate and the available luggage space so I did a rather good job of limiting myself). I'd never heard of the author before, but I definitely enjoyed the novel.
It's a mystery, but especially the second mystery that Adam is trying to solve regarding Emilio, never seems that hard - Adam has his suspect early on, and it's just a matter of finding clues to actually make it stick.
The novel is set in a villa near Florence in 1958. Adam, an architecture student, has the opportunity to visit the villa and write a paper on the beautiful memorial garden. The memorial garden hints to a hidden secret because while gorgeous, certain things about the set up just seem slightly off. While there, Adam also becomes interested in Emilio's death, the heir to the estate that died during the Nazi occupation. While the overall story was entertaining, I definitely preferred Adam's work in the garden, finding the hidden clues and symbols that represented an entirely different story than seen at the surface to the more modern murder mystery aspect of the novel. Of course, between the back cover and movies such as Quills, certain things seemed rather obvious, but it didn't affect the overall enjoyment of the story.