Orality & Literacy by Walter Ong: read it in grad school, opened my eyes to how writing and technology in general feed back into societies and can change them. Influenced my work in the early web in the 1990s.

A variety of books and essays by Mark Poster [https://en.wikipedia.org/wiki/Mark_Poster]. Fairly left on the political spectrum. Marxist analyses of technology and information technology specifically and how they can both benefit as well as oppress.

danah boyd [https://www.danah.org/] I enjoy her analysis & criticism of technology from a sociological perspective. She gave a great talk at one of the O'Reilly etech or web 2.0 conferences around 2009–2010 about how we were all building these great social media services with zero grasp of sociological implications. Like. By 2010 there was ~20-25 years of people being shitty online to one another in one form or another across The Source, Compuserve, AOL, Usenet, Fidonet, etc before everything shifted to the web. There were, and are, basic considerations to take into account when building an online "community" and yet time after time people are shocked, shocked to learn that people can be terrible online and that the services we build can amplify these behaviors massively.

I didn't find McLuhan nearly as useful as I was taught he'd be as the online world evolved into the web world. Prescient, yes, but I think moreso in a cheerleader for how great and wonderful the new world would be.