There are few Minitel-related books written in English. Here are two that we know of:
The Computerization of Society
The 1978 "Nora-Minc report" to the French President of the Republic, named "The Computerization of Society," was a landmark that helped define French telecommunications policy, and was the precusor to the introduction of Minitel in the eighties. Below is the picture of the English translation with an introduction by Daniel Bell.
The Minitel Saga: A French Success Story
The title of Marie Marchand's book says it all, though that view is contested by American critics, including Eli Noam.
Lots of self-help books were published in the eighties. These publications were intended to help tech-savvy users use a Minitel as modem for a home computer and to create a home server running one's own Minitel service.
Pierrick Bourgault, Minitel et Micro-Ordinateur (Paris: SYBEX, 1985)
Miguel Mennig, L'Indispensable pour Minitel (Belgium: Marabout Alleur, 1987)
Christian Tavernier, Les Secrets du Minitel (Paris: ETSF, 1985)
A 1991 letter from France Telecom to its clients lauding the French telecommunications system as one of the most modern in the world. Indeed, "[i]n 1989, Minitel made France the world's most 'wired' country" -- (James Gillies & Robert Cailliau, HOW THE WEB WAS BORN 111 (2000)).
The 1991 France Telecom Price list, including Minitel's access and per-minute prices. Connecting to the online phone book for 3 minutes was free (for multiple searches, one would just disconnect and reconnect every 3 minutes to avoid being charged), but the popular "3615" services, including the "pink-Minitel" chat rooms cost from 0.874 to 1.25 FF per minute -- (0.3 to 0.19 EUR per minute). Minitel was expensive!
One of the original overt motivations behind the Minitel project was to digitize the phone book and save money on paper, printing, and distribution costs. Ironically, Minitel became so popular that France Telecom started printing a paper-based Minitel directory. Pictured below is the 1994 edition