The core OLPC software is developed at http://dev.laptop.org/ using the GIT source code management system.
For the tasks of the translator, one needs to look into the different projects and locate any po/ subdirectory. The existence of this subdirectory show that the piece of software is internationalised (=can be translated).
For example, the core component sugar can be translated. In the main sugar page, and locate the po/ subdirectory that shows up. Click on it and you get the sugar po/ subdirectory with a few translations. Specifically, Yoruba, Hausa, Igbo and Italian. The italian translation is sadly useless. The translator made a mistake; he saw
and changed to (WRONG)
instead of (CORRECT)
Normally, one would need to regenerate the Template PO (POT) file before translating, instead of working on one of the existing translated files. To do so, one needs to download the source code of sugar using the git tool and then use intltool-update -P to create the fresh sugar.pot file.