Planning for both conferences is underway. If you are a woman and interested in joining the planning discussion, please get in touch with Wikimedia Argentina's Beatriz Busaniche, Wikimedia Portugual's Béria Lima or Wikimedia Australia's Laura Hale. They can help you get subscribed to the planning mailing list for discussions that do not take place on meta. Some planning discussions are taking place on IRC in #wikiwomenconnect. If you planning questions, you may also post them to the talk page for the conference.
From Ezeiza the fare will be something like 150-170 pesos. From Aeroparque will be around 35-45 pesos. Just tell the taxi driver the adress above, and if you want, you can try to fix he price (for that is better if you know how to speak Spanish).
From Ezeiza (EZE): take the shuttle Manuel Tienda León ("Tienda León" is the name in the shuttle - the price is 25 Dollars per person, and can be booked here). That will leave you in Terminal Madero, in Retiro. From there you can take a taxi to the hotel for ARS 25/30. But most shuttles can take you directly to the hotel for a bit more money.
From Aeroparque (AEP): In front of Aeroparque you can take the bus 37 (the bus pass in the two sides of the avenue, but don't cross it. Take the one in front of he Airport), and leave the bus in Rodríguez Peña y Corrientes, that bus stop is just after cross Corrientes Avenue. That is one street away from Bauen