Colombians are friendly and curious about foreigners so it shouldn’t be too hard to meet people. Look for street bars where people hang around outside and mill around.
You’ll get more educated conversation out of those from wealthier backgrounds but often they’ll have precious little idea of what life is like for other Colombians.
Colombia is a great place to improve your Spanish as there are very few tourists here and you’ll be forced to speak Espanol on a daily basis. The Colombians in the cities also speak some of the clearest Spanish you’ll hear anywhere.
Never say a bad word about the Catholic religion or Colombia unless you’re absolutely sure that you’re with someone very open-minded. The identity of most Colombians is carefully bound up with where they come from. To criticize and aspect of Colombia is to criticize them.
The street life can be fascinating with all kinds of street acts and performances as people try to make a buck. You’ll see kung fu guys waving numb-chuckers around in their efforts to recruit students and salesmen trying to flog impotence cures to circles of nervous men. Make sure, however, you’re in a safe neighborhood. It’s considered perfectly normal to ask at what time a place might get dangerous.
Nightlife in the more bohemian areas centers around bars that often spill out onto the street. This makes meeting people easier and they’re cool places to hang out and pick up. Also salsa bars and clubs are the core of Colombian nightlife and provide the perfect way to meet the locals. Helps if you can dance, of course.
For many travelers Colombia is the place to come and plug up their nostrils with cocaine, party until dawn and write incoherent postcards home to their friends about how often they get laid. That’s cool but don’t overdo it.