The main resources for localization and other info regarding KDE's localization teams is at the KDE Localization website. Please check there for more information.
For information specifically related to translation and translation teams, see the Get_Involved/translation wiki page.
Localization Team Management Tool (LTMT)
During the l10n BoF at Desktop Summit 2011, we realized that we had duplicated services and code doing the some thing (at least this was true for the French and the Italian teams): managing the translation process, mainly file booking.
So, we joined our efforts to have a good working tool to manage the translation process which could extend existing l10n.kde.org website and get the best from existing tools.
Internationalization (i18n) vs. Localization (l10n)
What is the difference between internationalization and localization?
Generally speaking, programmers internationalize their software by writing applications so they can be run in any locale. Translation teams localize software by taking the internationalized applications and adapting them for a specific locale.
The two terms are not always clearly differentiated.