Thanks to Holger Szesnat for sending over the link to this homepage:
I've added the link to my Scholars: U-Z page. Vassiliadis is at the University of Thessaloniki and he has made his homepage available in Greek and English versions. I am know him from his stuff on Q. The good news is that he has lots of full text reproductions of his own articles (though the font is absolutely awful -- you might need to copy and paste); go to his Detailed Bibliography and scroll down a bit.