Thanks to the Italian Minister of Foreign Affairs, it is quite easy to know if you need a VISA in order to enter Italy.

Using this website, by entering your nationality, your country of residence, your stay duration and reason for visit,  you will immediately find out whether or not a visa is required in your case.

In case you need one, here you may find out where to apply for it  in your country (it's the list of Italian embassies and consulates).

Finally, here you will find the costs for the VISA issuance.

Furthermore, immigration requirements are thoroughly discussed in English on the Italian State Police website (the State Police also acts as Immigration office) at http://www.poliziadistato.it/articolo...