Right now I am hunting unicorns in Brazil: looking for the hottest startups that are growing like 20%/mo.
First approach: my contacts. Ask people I know that deal with startups to point me which ones are good to go.
Second approach: SUP BRA - most influencial Brazilian community. You can reach them via Facebook: https://www.facebook.com/groups/supbra/
Fact: most Brazilians think we don't have good startups here. But it is not necessarily true.