Here are many websites that might help you find your ancestors in Argentina:

http://www.genfrancesa.com/extranjeros/buscador-extr.php
http://www.guiagenealogica.com/pasajeros.htm
http://www.barcoseinmigracion.com.ar/ruta.html
http://www.immigration-records.com.ar/index.html
http://www.genfrancesa.com/
http://www.bourlotcj.com.ar/lista.htm
http://www.cemla.com/busqueda.php
https://www.familysearch.org/search/collection/list#page=1&a......

Good luck!