You can buy the tracking apparatus and contribute to the coverage. Some friends in South Africa already do. I was thinking of it here (Gabon) as there is no tracking this part of the planet. But right now $500 is a bit out of reach. I would be able to pick up planes within a radius of 200nm equiped with ADS-B equipment see Automatic dependent surveillance-broadcast
“Flightradar24’s coverage is primarily made up of data contributed by volunteers from around the world. Roughly 1,000 aviation enthusiasts with ADS-B receivers regularly feed data to our network. You can help us increase the coverage in your area, regardless if you already own ADS-B equipment or you are interested in getting ADS-B equipment.”