如何在osx机器上安装php中使用的“locale”？

I'm developing a website that needs multilingual support. I am trying to use locales in php but a certain locale (es-CO) is not available in my development machine. It is on my hosting server. I've researched on how to add new locales but can't find how or where to get the new locale files. Should this be installed in the OS, on apache or on php? and where can I get these files? in linux i've found that running sudo-apt get language-pack-es-base does this but no idea how to do this in osx. Knowing how to do it in windows should come in handy also.I'm developing a website that needs multilingua