Chef Stuart Cameron of Trocadero in Chicago,IL recently sent me a list of books he would want if he were stranded on a desert island. One of those books is the Essentials of Classic Italian Cooking. This is considered a standard / classic cooking text, which is precisely why many chefs find it so valuable. This book is a combination of two books (both by Marcella Hazen): The Classic Italian Cook Book (first published in 1973) and More Classic Italian Cooking (published in 1976).
It covers in detail all the pillars of Italian food such as fresh pasta, risotto, gnocchi, scaloppini, bollito misto, and polenta. Be sure to try the recipe for baked polenta with meat sauce! But Italian food is not only comprised of these more common foods. Thankfully, Marcella includes fascinating recipes for unusual preparations (such as crespelle--a type of crepe and pesto prepared in the traditional mortar and pestle) and rarely used ingredients (sweetbreads, kidneys, squab, Jerusalem artichokes, etc.). In a day when Italian food is so popular and often poorly prepared, a comprehensive book like this one is essential to truly understanding one of the world's great cuisines.
Incidentally, the other books on Stuart Cameron's desert island list are: Larousse Gastronomique, Joy of Cooking, Kit Chapman "Great British Chefs", Alice Waters "Chez Panisse: Pizzas, Pastas and Calzones", James Beard "American Cookery", Ada Boni "Italian Regional Cooking", and Betty Crocker Illustrated (the 1950's version...NOT the modern one).