One way to chose to add Google translate to any languge to your blog is to do the following:
1) Create new link
2) For Name type: TRANSLATE TO ENGLISH (or to the most common language you expect that people will want to translate into and write it in their language)
3) For Web address copy this: http://translate.google.com/translate?hl=en&sl=es&tl=en&u=http%3A%2F%2FYOUR-WORDPRESS-BLOG-URL-GOES-HERE
In the above web address you must change the 'xx' in: "hl=xx" to your language code where 'xx' represents your blogs native language. Change the 'xx' in "sl=xx" to the language code that you think is most likely to be desired. In my example above I am converting from English ("hl=en") to Spanish ("sl=es"). For other language codes check the google translate website.
Note also that in the above example that there is an "F" before "YOUR-WORDPRESS-BLOG-URL-GOES-HERE" and you must NOT remove that "F" nor anything before the "F".
Now on the right hand side of the page Click "Add Link"
You are done. Test your page and look for your "links", find the translate button and press. If your reader does not want your chosen language then after the translate they will have the option to translate again into any other language.
I hope this helps