[1] Tomc spent his high school years in New York City, where he became a fan of Bob Dylan and developed an interest in rock'n'roll music.
Together with fellow sociologists Frane Adam and Pavle Gantar, he formed a working group within the Institute for the study of contemporary subculture movements in Slovenia and Yugoslavia.
During the Slovenian Spring (1988–1990), Tomc was active in many political and civil society organizations participating in the democratization process in Slovenia, most notably the Committee for the Defence of Human Rights.
In 1987, he was one of the 16 co-authors of the manifesto called "Contributions for a Slovenian National Program" published in the 57th issue of the journal Nova revija.
Gregor Tomc was, together with Frane Adam, one of the first Slovenian and Yugoslav sociologist to study the phenomena of contemporary social movements, with an emphasis of youth subcultures.