[ItalianStereotype]

hmm...that's not the easiest thing to tackle, Mod. until 1861 (1870 if you count the unification with Rome), there was no unified Italian state; it was a band of micro-states that lacked even the loose confederacy that the Holy Roman Empire had. if this is your topic of interest, my suggestions are:

The Prince
Origins of the State in Italy: 1300-1600 (VERY DRY READ)
Francesco Guicciardini's A History of Italy
The Rise and Fall of House Medici
Venice
Venice: The Hinge of Europe
The Renaissance Popes
The Borgias
Venice: City, Republic, and Empire
Pulci's Morgante and Medici Politics
The Pope's Elephant (I haven't read it, but I've heard good things)
Church and Politics in Renaissance Italy

that should give you a pretty solid basic knowledge of 16th and 17th century Italy, but I'll try to find more for you.