Anthology 
An introduction to systemless (freeform) tabletop roleplaying, and an overview of available resources.
http://membres.lycos.fr/sansregle/Dr. Game's Gaming Site
How-to-articles, presentations, scenarios, and a game in development.
http://www.geocities.com/dr_games/
The Forge
Dedicated to the promotion, creation, and review of independent creator-owned roleplaying systems. Also features discussion forums, articles about game design, and design resources.
http://www.indie-rpgs.com/
Introduction to Roleplaying
The basics, issues, and books.
http://www.geocities.com/daveshwz/
Land of Shadows
Short Introduction to Roleplaying.
http://www.shadowlord.co.uk/
Magister Ludi Roleplaying Resources
A collection of articles about GMing, with practical tips and advice, and a collection of roleplaying related links.
http://users.chariot.net.au/~amaranth/articles.htm
Random Dialogue: Gamemastering
Includes tips for Game Masters, a thesis on running Shadowrun games, and detailed campaign journals.
http://www.randomdialogue.net/gaming/gming.php
RPG Portal from Japan
Information about tabeltop roleplaying in Japan.
http://www.trpg.net/en/
RPG Tips
Tips, forums, and general information.
http://rpg_tips.tripod.com
RPG's and the problem of D3
A short introduction to roleplaying and a survey of the D3 problem.
http://www.boystoysreview.co.uk/rpg.html
The Handbook to Roleplaying
Advice for novice roleplayers.
http://www.angelfire.com/tx/afira/
Baldwin And Sheratan's Website
General site providing visitors with advice for players, game masters and those who want to create their own RPG.
http://www.aventures-arcanes.com/english/subdirectories/rpg_directory.htm
