Loads.
Germany and Argentina had been close friends practically since the German unification and even pre-WWI an immigration boom, particularly from Germany (Deutschargentinier), established themselves in the country in their own little communities with German schools and newspapers. And immigration only grew after the war since many sought to leave what they perceived as a broken German.
In fact, shortly after WWII under the new Perón regime Argentina not only welcomed fleeing Nazis but actually actively supported these "ratlines", collaborating with former SS Bond-villains such as Otto Skorzeny and his ODESSA network. Perón, as a military man, admired the Third Reich and fascist ideology of Mussolini, going so far as to call the Nuremberg trials something along the lines of a "grave error"... I can't remember the quote and it seems the Internet can neither. And he of course sought to use the expertise of Nazi fugitives to modernise his own military and industry.
Notable Nazi-Argentinians include logistics manager for deportation and extermination Adolf Eichmann, front man of the Ardeatine massacre Erich Priebke and famous mad doctor Josef Mengele.
On the escape routes from southern Germany and Austria through the Alps into the Italian ports, Nazi's frequently rested in the same inn's and guesthouses as returning refugees did. Jewish refugees were forced to pay higher prices for their food and beds than fleeing Nazi's did. So much for the loyalties on the escape routes! To escape from the ports in northern Italy to South America, Nazi's did need travel documents. But more than 5 years of war destroyed Europe and it was easy to claim that you lost all your documents. The ICRC and the Vatican provided people without passports with temporary travel documents. A simple statement about your identity from a fellow traveler was often enough to receive the documents. One Nazi provided a statement for the other one and so on. In that way loads of Nazi war criminals received their new identities. Bear in mind that civil administrations were often destroyed and Europe lay in ruins with more than ten million refugees on the move or in camps. Although the fighting had ended, the crisis had not and there was no realistic way to verify an identity.
If you are interested in the topic you should read "Nazis on the Run..." by Gerald Steinacher. Well written and very detailed. http://www.theguardian.com/books/2011/jun/24/nazis-run-gerald-steinacher-review