I'd like to translate the control panel to spanish, is the translation already available, if not, how could I collaborate to translate it?
Magento team have started translation project on this service
https://crowdin.com/project/magento-2
You can contribute to official translate there or make your own translation.
How to make language pack you can find there
Oh, thanks!, is this the one for magento 1 (I'm using magento 1.9.2.2 will it work if I traduce it all?)?
is that official? Why just argentina and not Chile?