Mechanical Turk is Amazon's take on micro-jobs. These are small miniscule-jobs that you can do for other people, which they call HITs, or Human Intelligence Tasks. These are super simple tasks that anyone can do. Some examples are listing off some URLs with certain kinds of images for one cent, or recording a few phrases with a microphone for 6 cents.
Like anything else in this world, you'll either need a lot of time or a lot of money. If you have both, then clearly, you're ahead of the game. But most people have more of the former rather than the latter. But considering that time is finite and we only have a certain amount of it, using your time wisely and managing your time properly is crucial to ensure your success.
Often, what happens is that we run into unscrupulous Internet Marketers (IMs) who have less-than altruistic intentions of extracting money from you rather than helping you to make it. However, this isn't something new. People have been falling for networking marketing, pyramid schemes, and affiliate marketing scams since before the start of the net.