GURPS Advantages, Disadvantages and Skills
   Collection of alphabetical listings of official Ads, Disads & Skills appearing in all published GURPS sources through November 1998.
   http://homepage.mac.com/bowman/gurps/ads/

GURPS Worldbook Index
   Complete index of every GURPS book ever published.
   http://www.sjgames.com/gurps/books/

Index of Official GURPS Errata
   An index of errata maintained by Steve Jackson Games. Includes every GURPS book ever printed, sorted by printing and edition.
   http://www.sjgames.com/errata/gurps/

The GURPS Library: Rated - A Consumer's Guide
   Game designer S. John Ross rates the quality of each book in the GURPS library.
   http://www.io.com/~sjohn/bigbest.htm