Where are you going to be staying? If the answer is "sometimes hostels", then you might want to think twice about taking a laptop. Even if you're always staying in hotels I'd leave the laptop home unless yoh have an absolute need for it, it's just something to worry about getting stolen/broken during your travels. If you need safe/secure internet access just bring along a bootable Linux CD find an internet cafe that will let you boot that on their machine (instead of using some potentially trojan infested public Windows machine).
It might be a lot less trouble for you just to buy some of the local pre-paid calling cards. You can find these all over the news agents there, they are cheap, and if you make sure to read the terms closely you can find really good rates. If you won't be making many calls then it might make sense to just buy one of the GSM chips that work worldwide and put that in an unlocked GSM phone (make sure it does900/1800Mhz at least). There are also some pre-paid calling cards that offer local access numbers throughout Europe, usually the rates are higher than the ones you buy at the local shops, but if you use it infrequently it could pay off in convenience.
Here are some links, the rates vary and these aren't neccessarily the best, but good enough to give you an idea. You should look around and compare on your own: