Argentina is a large country, the 8th biggest in the world in terms of area, and depending where you are, traveling from one river or lake to the next can take some time. Fortunately, there are regions where there is a solid concentration of fishable water. But be aware, for those without of a vehicle of their own, it can be difficult to fish in Argentina.
Hitching a ride on Ruta 40
Hitchhiking - Haciendo dedo
Hitchhiking is possible in Argentina, but be prepared to be waiting a while to be picked up, often between 1 or 2 hours per ride. At times it can take far longer than this, depending on the volume of traffic. Use of a sign is not necessary for hitchhiking in Argentina, an extended thumb is a sufficient signal to drivers that you need a ride. Be aware, the distances from one town to the next can be lengthy.
There are many competing bus companies found throughout Argentina, some of the biggest ones being Andesmar, Via Bariloche, and TAQSA.
A convenient website to purchase bus tickets in Argentina is Plataforma10.
Of course you can always buy bus tickets at local bus stations. The price of bus tickets fluctuates depending on the unofficial Dólar Blue exchange rate.
Buying/Renting a Vehicle
There are guides available on the internet that explain how you can buy a vehicle as a foreigner. One can be found here.
Note that only permanent residents and citizens of Argentina can transport vehicles out of Argentina. If you purchase a vehicle in Argentina as a tourist, there is a good chance that the Argentine National Gendarmerie (Border Control) will not allow you to transport it past the border.