Firstly, I suggest you go to the Argentinian Consulate in your place to find
out about paperwork, work permit ...
When are you planning to come down to this side? What are your plans? Where
would you like to teach?
In the meantime I figure these sites will be helpful:
You can also get in touch with the British COuncil in Argentina:
As you probably know, the economic and social situation of this country is
quite unsettling , but anyway, I figure it may be worth coming down to this
Best of luck in your search,