www.centraliapa.com - Ritamarie Long's website, which has an amazing panoramic photo of Centralia circa 1983, and rosters of former residents of Centralia and Brynesville.
Place Taste and The Taste of Place - An article by John B. Krygier, published in Globehead! The Journal of Extreme Geography (Volume 1: Thing 2, 1995).
Centralia, Pennsylvania - An offroad site with a collection of pictures of Centralia, Pennsylvania, the town with the mine fire burning under it.
Centralia Visit, July 1999 - Tom Gryn's page about his visit to Centralia, complete with pictures and descriptions.
Modern Ruins - A large collection of links about modern ruins.
Phillip Buehler - This was one of the first modern ruins websites I found. Photography-oriented links to other modern ruins sites.
Fix Buffalo Archives - Large collection of abandoned insane asylum links, as well as ghost towns and urban exploration sites.
Fear on MTV - Information on urban exploration and some handy tips and guidelines of what to do and what no to do when you go exploring.
Yaz's Hudson Valley Ruins - Links - The Hudson River Valley is loaded with abandoned sites, and Rob Yasinsac photographs many of them, and gives detailed histories of each. A lot of information on Briarcliff Lodge.