Sorry, if this has been answered elsewhere. I couldn't find one...
I plan to travel to Italy in a few months and was wondering if I can use my iphone's wifi and the Skype app to make calls back to the USA. If so, what plan do I buy?
Thanks for any help you can provide.

Unlimited US & Canada subscription @ $2.95/mo

you can use it when you return to North America as well (or from anywhere for that matter)

http://www.skype.com/allfeatures/subscriptions/uscanada/