As non-EU citizens you and your friends should be aware that the process of obtaining a work permit in Italy maybe a long one. So be patient.
It is best if you can secure a job offer before moving over to Italy. The easiest option would be to look into opportunities to have your current employer transfer you to Italy, if this is at all possible.Take a look at the Expat Arrival's page on Work Permits for Italy to learn more about the requirements for obtaining an Italian work permit.
If you are thinking about setting up your own business, it is worth bearing in mind that the work culture in Italy is very different to what you'll be used to in the USA. Have a read through the Working in Italy to find out more.
Finally, I'd advise you to take a look at this article - Getting a Permit to Live in Italy : One American's Struggle written by Jessica Spiegal, an American expat who was is a very similar position to yourself. I believe you'll find her insights useful and reassuring.
Good luck with your exciting new venture!