Lionel Messi, Gabriel Heinze and Juan Roman Riquelme all got on the scoresheet as Alfio Basile's side outgunned the Mexicans to book their place in Sunday's showpiece encounter at the Jose Pachencho Romero stadium in Maracaibo.
Argentina looked the most threatening in the early stages but it was Mexico who had the first clear chance when Juan Carlos Cacho took advantage of a defensive mistake but fired over the crossbar.
Javier Zanetti responded for the South Americans but the Internazionale midfielder shot weakly after creating an opening for himself, while West Ham striker Tevez went close minutes later after escaping the attentions of two defenders.
Mexico almost took the lead in the 35th minute when Andres Guardado hit the right-hand post before Tevez shot straight at keeper Oswaldo Sanchez after combining well with Riquelme.
Argentina broke the deadlock on the stroke of half-time, however, as Riquelme floated a free-kick into the box and Manchester United defender Gabriel Heinze acrobatically volleyed home at the back post.
Mexico coach Hugo Sanchez brought on Omar Bravo and Alberto Medina during the interval in search of an equaliser and they very nearly found it 10 minutes into the second period but Nery Castillo was unlucky to see his shot come back off the bar.
And it took a moment of magic from the masterful Messi on 61 minutes to finally break Mexico's spirit as the Barcelona star collected Tevez's pass on the right-hand side of the area and produced a majestic chip over a floundering Sanchez.
It got worse for the Central Americans four minutes later as Rafael Marquez obstructed Tevez in the box and Riquelme produced an audacious chip from the resulting penalty to put the result beyond doubt.
Substitute Rodrigo Palacio fired over when well placed and Messi saw an effort drift wide of the left-hand post late on as Argentina threatened a fourth and they will now bid for a record 15th title against arch-rivals Brazil.
Mexico, on the other hand, will contest a third-place play-off with Uruguay.