You can use this function Rand() and check for some boundlines of Italy like 46°,6° ; 37°,15° and after that check on Google API if that belongs or not to Italy. Not Easy, but can be done.
PS: Studing the coordinances of your country i think you can check all points above 37° and below 46° (north, south) and above 6° and below 15° (east, west). But the careful because there so many points and google will charges for more then a certain number of consults per day
Maybe start with generating a random postal code for each UserID:
Then use e.g. Google Maps API to find latitude and longitude using the postal codes / adresses.
Alternatively, you can also create randomly generated coordinates for e.g. an enclosing square of Italy, then maybe eliminate all coordinates in sea (which is probably the hard part). Maybe all coordinates that can't be translated to an address by the Google API.