GreekOrthodox.com
This site really helped me plan my trip.
Social networking based in greece.
It's got alot of cool information and an easy interface to use.
Account creation is minimal and getting started is a sinch. I recommend this one alot, Hope it helps any potential travelers out there.
I don't think it's based in Greece, from looking at the site. However, it is easy to sign up for the community.