Localisation files for CiviCRM: http://civicrm.org/
aka "using CiviCRM in another language than US-English"
Documentation on how to localise your installation of CiviCRM: http://book.civicrm.org/user/civicrm-community/localising-civicrm http://wiki.civicrm.org/confluence/display/CRMDOC/CiviCRM+Localisation
Internationalisation and localisation documentation: http://wiki.civicrm.org/confluence/display/CRMDOC/Internationalization+and+localization
Code of ethics: http://wiki.civicrm.org/confluence/display/CRM/Localisation+code+of+ethics
Localisation community building howto: http://wiki.civicrm.org/confluence/display/CRM/Localisation+community+building+howto
Transifex command-line guide for Linux: http://wiki.civicrm.org/confluence/display/CRM/Transifex+howto
Translation guide for Windows: http://forum.civicrm.org/index.php/topic,19068.0.html
For details on the release process: http://wiki.civicrm.org/confluence/display/CRM/Localisation+stack
For questions, please post on the Internationalisation forum: http://forum.civicrm.org/index.php/board,10.0.html
Or on the language-specific forums: French: http://forum.civicrm.org/index.php/board,58.0.html German: http://forum.civicrm.org/index.php/board,62.0.html Spanish: http://forum.civicrm.org/index.php/board,69.0.html UK: http://forum.civicrm.org/index.php/board,34.0.html