Iguazú: getting there
I must start this by saying that the name of the place to go is Puerto Iguazú in Argentina, at the very top of the province of Misiones.
You can also see the Falls from the Brazilian side, that is the city of Foz do Iguaçu.
Here I will only speak about the Argentinian side as I didn't visit the Brazilian one.
Taking a plane?
This city is one of the very few non-capital cities in Argentina that has an airport. This is due to the massive european tourist waves they get all year round.
It's a 1 hour 20 minutes flight from Buenos Aires. Beware of checking prices on the internet if you're not argentinian, as prices change for foreigners.
Aerolineas Argentinas and Lan are the two companies I know fly there.
They publish argentinian fees with a very suttle message that says those fees do not apply for non argentinians. So I would suggest calling or selecting where you passport's from in the airline's website.
Also, as far as I know, Lan does not take foreign credit cards.
If you book with Aerolineas Argentinas, don't be surprised if you're flight gets cancelled or delayed.
So I would advice not to book the latest flight in case you have to wait until the next day.
This doesn't mean, though, their service is bad.
If you need to stay at the airport for some hours wating for the next plane coz they've changed your flight for the next one, you can enjoy free food coupons.
Taking a bus?
If you do not wish to take another plane, the bus is the most used transport in Argentina.
So in this case, you'll have no problem in finding one or how to afford it.
Bus tickets do not change price, do not ask for documentation (except numbers maybe), and they're cheaper than planes of course (although not that much cheaper if you take into account the cost-last relation).
Not sure what to take?
While a flight Buenos Aires-Puerto Iguazú lasts 1 hour 20 minutes, a bus takes 18 to 20 hours to get there. Of course it's not constant driving.
Money wise, bus and plane tickets aren't very different. That's the strange thing of argentinian tranport.
Such long trips make stops in random places where you can buy things and go to the toilet. Although, of course this buses offer such services.
One of the stops is in San Ignacio where you can see the old Jesuit Order of San Ignacio's ruins.
This, of course, you don't see if you take the plane.
On the other hand, if you take the plane, the airhostess will announce when you can see a panoramic view of the Falls from the plane.
Leaving Buenos Aires
Buenos Aires has two airports so beware of where you think you're taking your flight from.
Ezeiza is for international flights, while Pistarini is for national flights.
So, it's this last one the one you take for Iguazú. It's in the city of Buenos Aires right next to the river, so it doesn't take long to get there at all.
You can even take a local bus.
Arriving in Iguazú
Puerto Iguazú's bus terminal is not any different to a normal bus station.
But it's airport looks more of a ski center than anything else. It's a nice little building with wooden windows and brick walls.
After you get your bags, make sure you get a place in one of the white vans waiting outside. They take you to the city where you can find loads of different places to stay.
There's one van per flight entering the city.
So beware if you're arriving in the latest flight of the day.
You must try to avoid taking taxis as they will charge you around 10 times more.
The airport is incredibly far from the city so you have to take something to get there, and there are no local buses from/to the airport.