Indo-European + ? = Greek

[Anastasios Helios]

I'm curious to discover the linguistical origin of the Greek language. To my knowledge, "Proto-Greek speakers" entered Greece around 2000 b.c. and merged with the cultures that already existed there to create the culture that we saw around time of the Trojan War. But does anyone have any knowledge about the cultures and languages that existed in the Aegean, Greece, Kypros, and Crete before then? I have heard rumor before that the original languages of Kypros and Crete were possibly of Egyptian/Mesopotamian origin. Also, there was a language spoken at Lemnos that was related to Etruscan....could these languages have belonged to a related family of non-Indo-European languages? Perhaps it constituted a culture and identity (Minoan for example) that existed and eventully merged with Indo-Europeans to form a "Greek" culture...can anyone explain this better to me?