Just a note of caution. I used a link in one of the above post and was directed to a google search which had a link that looked very similar to the address posted. Unfortunately it took me to a non-goverment site which stated the fee was $190 not $160 which gave me pause ( I will not muddy the water by posting that link)
I backtracked and found the correct link (as posted above)
http://www.migraciones.gov.ar/accesi...ciprocidad.htm
So a little caution would be wise