Citizens of United States of America do not require visas for travel to Argentina and as it is one of the visa exempt countries.
You must obtain visa from one of the Argentinian Diplomatic missions to visit Argentina. ETA for Argentina can be obtained by Chinese visitors who hold either a valid B2 visa (non-immigrant visa issued by the United States Government) or a Schengen visa with validity of more than 3 months. Citizens of Australia, Canada, Ireland and United States who hold diplomatic or service category passports need visa to visit Argentina. Passport holders of upto 88 jurisdictions can visit Argentina for up to 90 days without a visa. Passport holders of Kosovo, Nauru, Sahrawi Arab Democratic Republic, Taiwan, Tonga and Tuvalu require Travel Certificate issued by Argentina to visit the country. 
1- A recent digital photograph of the applicant.
2- Scanned color copies of your passport with minimum validity of up to 6 months.
3- Photocopy of your previous passport (if any).
4- Proof of the financial subsistence, such as your Income Tax Returns Certificate for the last two years or your Bank Statements of the last 6 months.
5- Accommodation proof of where are you staying during your stay in Argentina, or,
6- A contact address of someone you know in Argentina.
7- Copy of your Return or onward journey flight tickets.
8- Permanent address proof in your country.
1- Your passport must be valid for a minimum of 6 months from your date of arrival in Argentina.
2- There must be at least two blank pages on your Passport for entry stamp by the Immigration Officer.
3- You must have return ticket or onward journey ticket and sufficient money to spend during your stay in Argentina.
4- You must provide details of the hotel reservations for the whole stay in Argentina. The reservations must be under each applicant's name.
5- If you are staying with your family members or friends in Argentina you must provide a copy of their ID cards or DNI. The ID must be certified by an Argentine Notary Public (“Escribano Publico”) and then by the "Colegio de Escribanos".
6- You must submit your bank statements for the last three months as the Proof of Funds.
All Countries / Nationalities that required regular visa for ArgentinaApplication for the Long Stay / employments Visas, contact to these embassy below
Argentine Embassy in Washington, D.C., United States
1600 New Hampshire Avenue NW
Consular section: Edificio Sarmiento
1811 Q St, NW
Washington, D.C. 20009
United States
Argentine Consulate General in Miami, United States
1101 Brickell Ave, 9th Floor
North Tower
Miami, FL 33131
United States
Argentine Consulate General in Chicago, United States
205 N. Michigan Ave. Suite 4209
Chicago, IL 60601
United States
Argentine Consulate General in Los Angeles, United States
5055 Wilshire Boulevard, Suite 210
Los Angeles, CA 90036
United States
Argentine Consulate General in New York, United States
12 West 56th Street
New York, NY 10019
United States
Argentine Consulate General in Atlanta, United States
245 Peachtree Center Avenue, NE, Suite 2101
Atlanta, GA 30303
United States
Argentine Consulate General in Houston, United States
2200 West Loop South, Suite 1025
Houston, TX 77027
United States