After getting a monster international roaming bill ten years ago, I've been using the Flight Centre E-Kit sim card for overseas travel ever since (it's cheaper getting it from Flight Centre, than from the E-kit website). I use the cheap Explorer service, for phone calls and SMSs. Data looks too expensive to me.
http://www.flightcentre.com.au/trave...and-phonecards
My Association recommends this organisation, which I've never actually used.
http://www.roamingsim.com.au/
One hint - if you fly or drive through countries where you won't use the phone, don't turn it on, or alternatively, disable the SIM card in the menu, as some places are fond of sending you a welcome SMS and charging you a Euro or so for it.
Regards,
Renato