I'm a computer geek by trade, and a historian by training - so here's some interesting historical (or hysterical) links about geek stuff. (At least, they're interesting to me.)
Jargon File - ESR's archive of the Jargon File, as revised and updated by him and some other folks. Great resource for helping understand where we came from as a computer geek subculture.
See Figure 1 - A "customer service memorandum" purporting to emanate from AT&T, sometime in the late '70s or early '80s. An amusing take on the "spirit of service" in those days...
The Tao of Programming - an online copy of Geoffrey James' 1987 book. A classic in the field, so to speak.
The Hacker Crackdown - online copy of Bruce Sterling's book on the 1990 AT&T crash and the crackdown that followed.
Project MF - A working simulation of the old Bell System network, completely MF-able! (Translation - a phone system you can dial into and then control with multifrequency tones, much like the old Bell System network.) You'll need a blue box or another method of generating the tones to make much use of it - there are apps available for smartphones, or the ProjectMF site (and others!) has schematics for you to use to build a real blue box.
Telephone World - A great site about telephones and telephony, including a wide range of recordings. Especially wonderful are the collection of tapes made in the 70s and 80s by Evan Doorbell, now being digitized and narrated by him and released to the world. They're an incredible look at the phone system of those days and the phreaks who explored it.