For a US citizen who needs a Brazilian visa but is living in or visiting Buenos Aires, here is what i found. Also posted on my blog:

Here’s what you will need:

* A passport picture.
* Your passport, with enough pages in it to get a Visa. Mine had four remaining blank pages in it, which is not enough. The consulate first asked me to go to the US embassy to get pages added.
* Travel plans- copy of your hotel reservation, copy of your plane ticket reservation. If you don’t have a return ticket yet, you could consider making one up - just make sure you have something that looks like a valid e-ticket summary from a website. They don’t particularly look closely at these documents.
* If you are getting a Business Visa, you will need a FAX from the business you are going to be working with when you are in Brazil stating the purpose of your trip, and what you will be doing. It is also important that the fax state that you are not working for that company while you are there.
* They told me for the fax that it must come from Brazil, but it turned out this wasn’t possible for me (their fax was down), so I just had the company fax me the letter, and I re-sent the fax from my own fax account in the US. They did not have a hard time with this.
* They did not ask for bank account information but they say on the website that you must provide this, and I saw other people were being asked for this information.
* When you enter the Consulate, go straight up to the window in the center. They speak English if that’s an issue for you. First, tell them what you want and show them all of your paperwork. The reason for this is that if you are missing something, you won’t waste the 10-15 minutes typing up your application on the computer only to find that you don’t have the necessary items.
* If you don’t have a picture they’ll give you directions to a Kiosko around the corner that will take it for 13 pesos.
* Once you’re sure you have what you need, go to the computers to the side of entrance, and type up your information. You’ll need mother’s/father’s names, address of your hotel or residence in Brazil, phone number where you can be reached, etc.
* Then get in the line to the far right for Tourist Visas.

Important things I learned during my FIVE trips to the Consulate:

* If you are going for a conference DO NOT tell them this - simply say you are going as a tourist. According to the Brazilian consulate in the US, attending a conferences is OK under a tourist visa, but according to the Brazilian consulate in Argentina, this is a business activity and you need a business visa. So, if you want to avoid hassle, keep it touristy.
* Unless you have a DNI, DO NOT tell them you have residency in Argentina if they ask. You will then be forced to show your residencia, etc. This is especially true if you are getting a business visa, because then they will want proof of your company in Argentina, (ie do you work for an SRL - like an LLC in the US). If you simply put your US address on the application, they won’t ask any of these questions.
* You don’t need to bring any money; they will give you a receipt and directions to the Banco Itau where you can pay. You must bring this receipt when you come back to pick up the Visa.
* The Visa takes 3 days. I dropped mine off on a Tuesday and picked it up between 12-1 pm that Friday.