Howdy,
Just got back from 6 months in South America.
So we didn't do an exceptional amount of climbing but here is what we found:
Columbia:
Suesca near Bogota is good for trad, but nothing world class in my opinion. There are heaps of multipitch climbs there and some sport (pretty run-out bolting though).
La Mesa de los Santos (in La Mojarra) is one of the most awesome sport cliffs ever. The cliff comes into the shade after 11 am which is perfect because it gets pretty hot and the bolting is really good.
Be warned if you go to do any climbing at sea level in Columbia, it is unbariable hot.
Peru:
The most climbing options are in the cordillera blanca near Huaraz. There is a sport climbing area called Hatun Machay. The argentian bloke that has set up the area reckons its the next ton sai, but he is bloody dreaming. However there are some good climbs. We were there in the rainy season, which majorly sucked. The rock was so cold our hands were so numb we could barely climb. The area is also at altitude (4300m) which made climbing interesting.
There are supposed to be granite cliffs to trad climb in the area. I think a very well known climb there is called the Sphinx.
Bolivia:
Haven't heard of much climbing in Bolivia. If there are an sport areas I'd be cautious of there bolts. The well known bouldering area is called Valle de la roca. This area is in the Solar de Uyuni and hence is very dry and at altitude.
Chile:
One of the most beautiful places on the planet - Cochamo Valley. Its a real mission getting into the place but its described as the Yosemite of South America. Huge granite cliffs surround the valley, there are waterfalls everywhere and a beautiful river running down the middle. An american guy, Daniel, has setup a refugio and has a website that has plenty of info on the area. The area does get a lot of rain so climbing is best Jan-Mar.
Argentina:
The area around Bariloche has many climbing options. Frey, a bit of a walk from town, is beautiful and has heaps of trad climbing on smallish granite spires. The place gets a lot of snow so climbing there is also best Jan-Mar.
Have a great time over there and don't miss the rafting near San Gil, was awesome on some class 5 rivers.