Good place to get a Italian sim card (with a fair amount of wifi) for my girlfriends samsung phone.

I generally go to a Vodafone store or authorized electronic store (Vodafone is a major mobile phone provider in Italy) and purchase a SIM Card with the Vodafone Holiday plan, which is designed for foreign visitors. The cost is €30 for a month. Details are below.
http://www.vodafone.it/portal/Privati/Tariffe-e-Prodotti/Tariffe/Estero/Vodafone-Holiday-English

You can locate a Vodafone store or authorized dealer (rivenditore) below. Enter Roma in the search box, although I think the map shows Rome by default.
http://trovanegozio.vodafone.it

TIM, another major provider, has a similar plan. I don't use TIM because they don't have good 4G coverage in the area of Tuscany where I have a country house, but in Rome any provider will have good coverage.

You will need to have an unlocked phone to do so. If you purchased your phone with your provider (eg AT&T, etc.) the phone is likely locked and they will unlock it only if fully paid (generally after two years).

Thanks I will look into that, it is an at&t phone, but is unlocked (we use it with a different provider). does vodafone (really bad reviews about tim I think if I remember right) have a good connection? we don't want to have it quit working because we are in a tight ally or something.

Interesting...I had the opposite experience with TIM..worked very well in my travel through Tuscany and north Italy. Bought a cheap TIM phone several years ago and have swapped out the SIM cards for Portugal and Spain SIM cards(saved the Italy card for next visit in May)
But that was for local phone service,not data.
I use the Wifi on my android phone which I bring for that purpose. I have never had a situation where WIFI was not available even in the smaller, family run accommodations that I use.

It's not a Vodafone issue. Italy has old masonry buildings where walls may be very thick, up to 2 or 3 feet thick, like a bunker. I sometimes have to be near a window to get cellular signal, especially in the lower floors. In the outdoor, it shouldn't be much of a problem.

The only place i didn't have free WiFi was at my B and B in the mountains of Amaseno (Frosinone, Lazio). In that case i found a neighbor who had WiFi and was willing to share his password. I'd carry a chair from the B and B patio to the alley, put my MacBook Air on an old unused stone stoop across from the neighbor and set up shop outside!

Vodafone and TIM are the largest providers, and their coverage in rural areas may vary. Overall Vodafone has the most extensive 4G LTE coverage in Italy, but TIM is not far behind. In some places one might be better than the other or viceversa. My country house is not covered by TIM at all. In other localities the opposite might be true and TIM might have better coverage. It depends on where the specific provider has the closest cell tower. The best way would be to check below by inserting the name of the municipality one is interested in the website below.
http://www.tariffa.it/copertura-rete-mobile/
But although local coverage may vary, if you zoom out on the map, you will notice that on a national level, Vodafone has the most extensive 4G coverage.

In a large city, all providers will have good coverage.

we aren't quite as worried about getting the free wifi in our Room, as much as having it available where ever we happen to be each day.

Recommend that you go to a store in a major entry point such as city train station. I went to a small city Vodaphone store and wound up needing to return twice with continued problems until getting everything straightened out at Santa Maria Novella in Florence. The other store was unfamiliar with the 30 Euro promotion and activated the wrong plan. Another 15 Euro gave me the correct service because the plan could not be changed but 3Gb data could be added. Frustrating, but lesson learned and next time I will take a print out of the plan to show the agent in the store to minimize language barrier issues.

I will probably have to just go to a store, we don't plan on needing to go to Termini at all I don't think, unless we do a daytrip which wouldn't happen until at least a week into our stay.

Free WiFi is commonly available in ristorante in large cities and other well travelled places. I was also told libraries but I've not been. I've used terminals in computer stores in larger cities, but I couldn't do what i needed on their equipment. They are small stores with access to terminals. One is near Termini and if i could recall the name I'd say it here. Also if free WiFi is not in your room, it may be in the lobby.
In small hill towns like Amaseno, free WiFi may be available outside in the village square, this was at the base of the mountain in Amaseno, only I could not use my US iPhone to access the WiFi because of cost issues, I had to use my Italy TIM cellphone to text a number to receive the WiFi. Sprint had told me not to text or call on my US plan, i could only email from Italy.

I bought my TIM cell and plan at the TIM store on the upper level of Termini train station in Rome. A great store, one clerk spoke good English and made it easy to get set up on a TIM plan.
I should check into Vodafone! My TIM plan is 50 Euro a month, kinda pricey!

I am hoping to use the TIM Card (if that is the one we decide on) in our smartphone, we really don't want to have to rely on wifi.

I was in Palermo in June and went to a local Vodafone store. I got the holiday plan described by Roberto above. At the time it was 20 euros for 3 gbs of 4G data and 300 minutes of calls that could be used for local calls or to call back home to the US.

Took a total of about 40 minutes but 15 of that was waiting time. My Italian isn't the best and the clerk had limited english but we got it done. She inserted the SIM card for me as I forgot to bring a paper clip. She also gave me a sim unlock PIN number and told me to wait an hour. An hour and a half later I restarted my phone and after a couple of attempts was able to use the PIN code to unlock the SIM card. Moments later I got a series of texts from Vodafone and I was up and running.

It was my first time traveling with a smartphone and I found it useful. I find that hotel wifi is unusable about 10 to 15% of the time so being able to use the hotspot feature on my phone to connect other devices was quite a benefit.

When I got home I reinstalled my old SIM card, restarted my phone and I was back in business with AT&T. I was dreading having to mess around with changing APN settings and such but neither Vodafone nor AT&T required it. I suspect this may not be necessary with newer smartphones as the SIM card sets it, but I could easily be wrong.

Edit: My post was the one causing the issue. Somehow it was identified as potential spam and removed. I contacted the webmaster and it was corrected. Sorry for the weirdness.

So i am getting email notifications showing 2 replies in the last couple of days that do not show up on the thread. any Idea what is going on?

I think you get pinged if someone goes in and edits an earlier response--to correct a typo, for example.

no, it shows me the comment in my email (must have deleted the first one) but it is not here in the thread

Then perhaps the writer deleted it. Or maybe it's in your private messages.

I got another email saying the same message again, and now I can see it here. Strange.