Legitimate work at Home Assembly Jobs

FORTUNE — Dear Annie: I was interested in your column about how to get back into the workforce after a long time-out to raise kids. I’ve been a full-time mom for four years and would like to pick up my career where it left off, or at least try to get my foot in the door somewhere. I’ve been wondering whether it would be possible to work from home for now, since my children are still pretty small, but I keep hearing that most work-at-home jobs you see advertised are frauds. How can I avoid getting stung? Most of my work experience is in customer service. Can I find a legitimate at-home job in this field? — Mary Lou

Dear Mary Lou: Thanks largely to the Internet, the number of people working from home in the U.S. has skyrocketed to over 4 million. Between 1998 and 2008, according to New York City tech advisory firm Nemertes Research, the “virtual workforce” grew by 800%.

Still, you’re right to cast a skeptical eye on job ads that make lavish promises since, as with any fast-growing and hard-to-regulate field, this one has attracted its share of con artists.

So how can you tell the good guys from the bad? Researchers at RetirementJobs.com, a job site specializing in employment opportunities for people over 50, recently put together a guide to working from home, available online to its members, that includes 10 warning signs of a possible scam. Beware of “employers” who:

• Don’t clearly describe the work you would do.
• Require advance payment for a “starter kit” or “handbook”
• Won’t allow you to speak with an actual person
• Promise high earnings for little work
• Rely on testimonials depicting attractive, happy people or families
• Depict lavish homes, cars, and boats
• Feature large quantities of money in their ads
• Have a record of complaints for fraud (Check the Federal Trade Commission’s web site, as well as state counterparts.)
• Promise to eliminate your financial problems