Wild camping is possible but not as widely accepted as it is in Chile. A number of Argentines have recommended to take caution when wild camping just outside of a town for safety reasons. If you are in rural areas, you shouldn't have any problems. Quite a lot of land in Argentina is privately owned which can make wild camping a bit complicated. You can always try to ask a landowner if they will allow you camp on their property.
A friendly street dog may follow you for hours then sleep outside of your tent at night
Paid Camping Sites
Argentines love to camp which is evident in the number of campgrounds found throughout the country, normally costing anywhere from $4-8 USD per person per night. In some cases they are free. Most towns have at least one campground, either located within the town itself or just outside.
Do your research about the status of camping in the national parks if you intend on visiting one. It was not possible to camp in National Park Los Alerces in 2014 because of a Hantavirus outbreak amongst the mice in the park.
The bigger cities and towns in Argentina usually have hostels. Wifi is free and most have public kitchens available for use. The rates may range from $8-14 per night for a dorm bed.