Easy to find an unlocked cell phone here (best price for used) or in Europe.
I'd suggest getting national SIMs (i.e. one for each local country) if most of your time is in one or two countries or an international one if you plan to spend equal time in more than two countries.
e.g. you are spending most of time in Italy and Germany but a few days in France and Austria - get an Italian & a German SIM and use one or the other to roam in the other countries.
you are spending about the same amount of time in all those places - consider an international SIM.
Cheapest rates - National SIM in that country but could be wasteful if you don't use all the minutes before moving on.
PM me for any additional info you need on phones, service, etc. or read my posting in Technology on Cell Phones in Europe.
As to internet phone service, it is wonderful IF you have your own computer and free wi-fi. Software is free, runs on PC, requires earphones and mike and calls anywhere are dirt cheap. But if you pay the outrageous charges some places ask for wi-fi or internet, it is foolish to use it.
Again, PM me if you are bringing your computer. I can tell you exactly what you need.