Hello there!
At first, sorry my English. I`m Russian and I translate SliTaz to Russian. And I tell You all, that I know about translation.
What You can not yet translate? Home-made scripts (box`es, dialogs), because they needs a internationalization (i18n) first (yes, You can translate it now, without i18n, but it`s monkey`s work). All other You can translate.
SliTaz not supports Turkish out-of-a-box. And haven`t locale-pack for it.
You may translate '.desktop' (in /usr/share/applications/) and '.directory' (/usr/share/desktop-directories/) files. Read about this files format at http://standards.freedesktop.org/desktop-entry-spec/desktop-entry-spec-1.0.html
After this You can see new localized items in desktop`s menu, if You correct set Your locale.

Then, You can translate gettext-based apps. You want to install gettext and poedit.
There`s two formats of strings files: po and mo. In /usr/share/locale/your_lang/LC_STRINGS/ You can see mo (machine strings).
You can convert all of they by command line (in this folder)

 msgunfmt filename.mo -o filename.po 

and in back way (from 'po' to 'mo')

msgfmt filename.po -o filename.mo

You may search specified already translated files in net: po in source tarballs, and mo in binary packs (also see links in pkgs.slitaz.org to project`s homepages).
If not, You can use specified file from other lang, say, France. Convert 'mo' to 'po', copy 'po' to Your home dir and open it in poedit. Fill Your name and email in fields about translator; and fill lang in directory info.

After translation You want save [Ctrl+S], and poedit auto-generate 'mo'-file (with default poedit`s settings). Copy this 'mo' to Your /usr/share/locale/tk/LC_STRINGS/ dir. Overwrite old one, if need. Start the translated app (or restart X, if You can't close app, like LXPanel). See Your new translated app! Check the translation. Correct it in poedit... And again...
If You have translate all the strings, but You see untranslated ones in app, may the original 'mo' was old. Try to add this string to 'po'. Open it in LeafPad and write this string. It`s easy!
That`s all. Good Luck!

Lexeii, а можно это все теперь по-русски пожалуста, или отправь мне на мыло geniybk@mail.ru, заранее благодарен

to geniybk:
I don`t know, how we can feel free to speak Russian in English branch of Forum. Therefore I posted to my blog http://lexeii.blogspot.com/2010/05/slitaz-1.html (in Russian)

2 geniybk:
Я не знаю, насколько свободно мы можем говорить по-русски в английской ветке форума. Поэтому я описал эту тему в моём блоге http://lexeii.blogspot.com/2010/05/slitaz-1.html «Переводим SliTaz на русский язык. Часть 1» (читаем по-русски).