I got a SIM for use in Spain only and no Internet for 10 euros at Vodafone! I can still use the Internet at any fee wi-fi spot and there are plenty if those in bars and hostals and albergues. It was 5 more euros because my iPhone uses a nano SIM. You can recharge the SIM for time at any tobacco or phone store. This is a much cheaper option than using AT&T from home. For calls to home I will use FaceTime or Skype FREE at wi-fi spots.
There are still locutorios everywhere we have been on this route so you can make inexpensive calls home from those if you wish. For emergency calls TO you from home, have your family use the supplied lodging list (for my AnnieWalker folks).
You must have an unlocked phone. If you aren't sure, call your phone company. They actually gave joe a phone last year but I think you can buy a flip phone for 20 euros or so.
The girl at Vodafone spoke great English.