The Witcher

The Witcher is an action role-playing video game developed by CD Projekt RED and published by Atari. The game is based on the book series of the same name by Polish author Andrzej Sapkowski ([1]).

Most interesting links I used during the game:

gamefags.com

• The Witcher: Talent Tree Analysis by Harleyquin2008

http://witcher.wikia.com

• Maximizing Experience Points (witcher wikia)
• Cheapskate's Guide (witcher wikia)
  How to get the most and spend the less
• Guide to romance in The Witcher computer game (witcher wikia)
• Guide for illiterate witchers (witcher wikia)
  Information one can collect throughout the game, but excluding books.
• Witcher library guide (witcher wikia)
  List of all books in the game, where to find them and whether they can be obtained for free, etc.
• Shopping List (witcher wikia)
  All the things to collect / to do in the game

http://witcher.wikia.com also has many other pages on quests, food and drinks, weapons, etc.