
The Federal Trade Commission has put together a pretty good article about work from home scams. Many of the ads you see out there sound too good to be true. A lot of them are. Some of course are legitimate opportunities, while others want you to shell out money for information and startup costs. Not that if we're talking about starting a business, there might be legitimate startup costs. You should not, however, have to pay someone for a job.
Remember to use common sense. If someone is telling you you can make thousands of dollars while sipping margaritas on the beach, there's probably something they're not mentioning. There are legitimate opportunities out there, but they do require you to work. Do some homework. Look at a bunch of different opportunities before making a decision. If there's a significant investment required, make sure you get lots of references. Remember, if it sounds too good to be true, it probably is.
FTC: Work at Home Schemes [1]