There is a wealth of knowledge about AT&T Long Lines, towers, cable routes, and the like on the Web. During my research, I have found these particular sites to be of particularly high quality, with excellent content and involved maintainers. I would strongly encourage you to thouroughly examine them for hours of enjoyment, exploring the rich history of communications and the vast realm of technology currently in production.

• Long Lines by Albert LaFrance - the definitive source for maps and site profiles from the Long Lines era.
• The ColdWarComms Mailing List - A mostly on-topic discussion of communications, primarily of Long Lines era topics.
• Telebeans.org by Parris B. Wood - a site covering a broad range of communications topics, with a maintainer eager to help the community of those with similar interests.
• Berkana Wireless Radio Tower Locator - a versatile search engine for FCC ASRN data.