All types of ceremonies are possible in Italy. Civil and Catholic ceremonies just require a bit more work and expert guidance. A symbolic wedding can be religious or secular but it has no legal standing. There is nothing easier than a symbolic wedding since no documentation is required. The officiant could be anyone, it could be a friend or a relative or we can arrange for an officiant. With a symbolic ceremony you would need to have a civil wedding where you live before coming over to Italy. I once had a couple who ran off to Vegas for their legal wedding a few months before their symbolic wedding celebration in Italy. The majority of weddings in Italy are symbolic.
But some couples really want to have it all in one and are willing to do the work and jump through the hoops required. As mentioned if taking this route it is important to have someone experienced and diligent in Italy to guide you through.
A strictly civil ceremony can usually only take place in the designated civil hall of any given city or town in Italy. Fortunately the Italians are romantics and they usually dedicate one or several of the most historic and beautiful locations to civil ceremonies. Occasionally a town will consent to having the civil ceremony at your private villa but that depends on each town and this is more of an exception than a rule. Your experienced wedding planner can guide you in choosing the right villa if this is your strong preference.
The steps required vary by country but for the US and almost every other country the first step is to contact the Italian Consulate with jurisdiction over where you live to ask what is required. This will certainly include original copies of your birth certificates and an apostille (an international seal that can be requested online together with the birth certificate). Other documents may be required and vary with each consulate, particularly if either of the spouses have had a prior marriage.
To your appointment at the Italian Consulate you will be required to bring with you 2-4 witnesses (it varies according to the consulate) who are not family members. These witnesses will be swearing under oath that you have no impediments to marriage according to the law. The Italian government will not be verifying whether either of the spouses is already married to someone else or whether the spouses are first cousins who are not allowed to marry by law. Your witnesses will be testifying on your behalf under penalty of perjury to this end.
There are Italian Consulates throughout the US in NYC, Washington DC, Miami, Philadelphia, Boston, Houston, Chicago, Detroit, San Francisco, Los Angeles, Here is a link to the consulates in the US which also lists the jurisdiction of each location. If you live in Mississippi, for example, you would be required to go to the Miami Consulate to provide sworn testimony to the consular officer there. You cannot choose to go to Houston instead. https://ambwashingtondc.esteri.it/ambasciata_washington/en/informazioni_e_servizi/la_rete_consolare
In addition most foreigners should plan to arrive in Italy at least 5 days in advance as they will be required to do a “nulla osta/dichiarazione giurata” (a sworn statement) with a notary public at the American Embassy in Rome, Florence, Milan or Naples. These appointments must be made in advance and for most locations are only available on Tuesdays and Thursdays although the US Consulate in Naples schedules appointments every morning, Monday - Friday. (If you are curious as to why Naples it is because there is a large US military base nearby and so there are more Americans living in the vicinity in need of consular services).
I always say that getting legally married in Italy is not difficult…the second time. It requires patience, precision and guidance. The hardest part is the Italian Consulate in the US. You are in luck if you live in a city where there is a consulate, such as San Francisco, it is much easier for the couple to have a legal wedding in Italy. There are a series of appointments that need to be schedule with precision and failure to fulfil any of these will result in not being able to get legally married in Italy. The process can begin up to six months before the wedding day.