You need to do a little more reading about viruses before you decide that one's a man-made, conspiracy-driven creation. For one thing, it's much older than you realize (read the link below), and it pre-dates the days when virus-engineering was even a possibility.
AIDS origin - Wikipedia, the free encyclopedia

Scientists know how viruses like HIV begin in the animal population, and they're fairly certain that particular one originated in primates. If you learn a bit more about viruses, you'll learn that the most deadly ones we know originate in animals (influenza, bird flu, Spanish flu, smallpox) and mutate until they're able to make a jump to humans. If HIV were a human creation designed to annihilate an undesirable portion of the population, then why have there been such government-supported advances in the medicines that treat it? Why would the governments and scientists even have bothered?