For any soon-to-be Argentine newcomers, I recommend getting your prints in the States, especially with the extra waiting time from the Apostille required from the US Department of State.
The FBI received my prints and request (according to the ceritfy mail stamp) on April 1, 2010. Then, my parents got the fingerprints rejection letter at the end of JULY. I have hunch it will be easier to at least get those prints in the States if you can. The Embassy here is totally unhelpful even though they have digital print machines on site, except to send you to the same Arg police station who do their best to take the prints. When I was in the station, I met another girl with her fingerprints rejected by the FBI!