Applying for a Permesso di Soggiorno. USA or Italy?

After further research I discovered:

"Resident

Americans staying in Italy for more than three (3) months are considered residents. This includes Americans who will work or transact business and persons who want to simply live in Italy.

Americans must have an entrance visa which should be obtained at an Italian consulate before coming to Italy, in order to remain in Italy more than three months and gain resident status. This procedure will take several weeks to complete so it is advisable to apply well in advance of the departure date. The visa will be granted only for the time indicated on the application. Americans already in Italy without a visa will have to leave Italy to obtain one before they will be able to gain resident status.

Upon arrival in Italy, the American must obtain a permesso di soggiorno (permit of stay)."