Following are five free ways to crowdsource useful information needed to close your investigation. With 2 billion users online and more viewers on Facebook then all evening news shows combined, the Internet can serve as your own eyes and ears to find offbeat information. It's a tactic that can't be skipped.

In and we used the vast database of the Internet to search for unknown and anonymous data, but with crowdsourcing the answers we need come to us. Instead of searching for known data online, learn to ask the world for help. And then know how to interpret or verify the information you receive.

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With all these tools, you must remember that anything you post essentially becomes public information. Don't post details that could compromise your investigation. (More on this cautionary note at the end of this column.)

. One of the oldest (and often most humorous) sites for crowdsourcing information is Yahoo Answers. Although the site is simplistic in setup and presentation, publishing a question and getting a serious answer is quite possible. Yahoo still draws a big crowd. From basic questions like "What year was the first computer was produced", to more advance questions regarding cybercrime, Yahoo Answers can quickly provide you that data that no search engine will ever crawl and collect.