There are a few things to know about traveling to Sicily. One, you should really budget a good two weeks if you really expect to take in everything the island has to offer. Two, a tour of Sicily is primarily a tour of its coastal areas; although there are some terrific inland locales to visit. The ultimate Sicilian vacation would take you all the way around its circumference.
The starting point would be the exotic, chaotic capital city of Palermo, after which you could head west to Trapani and Marsala, or, more likely, east to Cefalu, Messina, Taormina, and Siracusa. If you have the time, try to budget a day or two on the Aeolian island of Salina (where Il Postino was filmed), where the caper berries grow as big as grapes and the seafood is among the best you’ll ever eat.
Palermo feels like an exotic capital city, as it is a major port town with gorgeous food markets, especially La Vucciria market, down toward La Cala harbor. A Moorish influence is evident in both the architecture and the food of Palermo, so the restaurants have a very different feel here than even the rest of Sicilia.
If you choose to go west, up around the horn to the northwestern coast, lies Trapani, mostly known for its sea salt and access to the ferry boats that will take you to the paradise islands of Lampedusa and Pantelleria. The food is simple in both Trapani and the islands, but the language becomes an issue in all three places. I myself have had serious difficulty understanding both the accent and the dialect in these areas, so be prepared.