There are lots of great Drupal resources available. You can participate in the groups and forums, hop on IRC, read the documents and articles, and watch the videos!
Internationalization group:
groups.drupal.org/i18n
Translations group:
groups.drupal.org/translations
Translations forum:
drupal.org/forum/30
IRC channel:
#drupal-i18n
Multilingual Guide:
drupal.org/documentation/multilingual
HowTo: Basic Internationalization setup:
drupal.org/node/1268692
Translate Drupal to your language:
drupal.org/contribute/translations
Localization API:
drupal.org/node/322729
Module developer's guide (Multilingual support):
drupal.org/node/303984
Internationalization module APIs:
drupal.org/node/1114010
Developer cheat sheet:
hojtsy.hu/files/Drupal7TranslationCheatSheetv2.pdf