Secrets of the Little Blue Box (1971)
lospadres.info
lospadres.info
Exploding of course gives much more information on the subject of phreaking to anybody interested.
The author maintains a database of all the source documents he used to write the book on the books website, which is fascinating in and of itself:
"A telephone isn't private anymore. You can't say anything you really want to say on a telephone or you have to go through that paranoid bull----. 'Is it cool to talk on the phone?' I mean, even if it is cool, if you have to ask 'Is it cool,' then it isn't cool. You know."