For Lap tops the picture isn't quite as rosy at least if you didn't buy your laptop in Greece. I had a Toshiba Satellite that I had bought in the US. I got the extended warranty because I knew I would be moving to Greece and I also knew there was a Toshiba dealership here in Athens. Unfortunately 'to service' was way down Syngrou Avenue and rather inconvenient. It wasn't free either by any means. Plaisio would service your laptop too if you walked in to the service center on Notara street with it. You can also by laptop stuff on Stournari Street and there is an Apple computer store there too.
If you aren't fortunate enough to have access to Athens I think you'll still be able to get want you want if you try but Athens is the best bet all around for solutions. http://www.plaisio.gr/ is one on-line option but to get a better on line overview of the Greek electronics market use the in English Greek search engine Robby.
Stournari St. is also good for watches, cameras and cell phone stores. All the larger stores including plaisio sell cellular phones but Vodaphone and Cosmote have branches there too.
Since I wrote the above the advent of the Netbook has changed our lives and I bought one for my mother's nurse for Christmas for 299 euros so she could commune with her people back in the ex-soviet republic of Georgia. She loves it and watches Georgian TV on it all the time! This is after I taught her about F11 for full screen and ctrl + she can actual see something on the smaller size screen. These Netbooks are pretty good if you can get used to the smaller screen and dinky keypad!
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