Well, it is really hard comprehensively to tell about Turkey, a beautiful country resides on the Anatolian soil of thousands years of history. As a tourist or knowledge admirer, you would need the best sights including ancient and modern ones, great accommodation coverage (hostels to hotels), Turkish cuisine, traditions and surely a bit of language to communicate.
There are surely also other books covering Istanbul, Antalya and other major touristic cities separately but Turkey Country Guide