Better Business Bureau is advising social networkers to read the fine print when responding to ads on Facebook or other social networking sites because the large print doesn't always tell the whole story. Ubiquitous ads for weight-loss products, work-at-home opportunities and offers for "free" computers can cost shoppers more than they bargained for in the long run.

According to Nielsen Online, social networking sites were more popular than e-mail in 2008. Facebook's 108.3 million members spent 20.5 billion minutes on the site last year. Advertisers are going where the people are, and eMarketer estimates that $1.3 billion will be spent on social networking advertising in 2009.

People need to use extreme caution and read the fine print before handing over their credit card information to an online advertiser. Just because an ad appears on a Web site they trust, it doesn't mean they can always trust the advertisers. One of the big red flags we're seeing is ads that link to blog platforms designed to look like a personal testimonial from a satisfied customer. In our experience, if an ad takes you to a blog, it's best to hit the back button immediately.

The following are just a few examples of common ads on social networking sites and what the fine print reveals:

THE PITCH: LOSE 4 DRESS SIZES

In January, BBB issued a warning to consumers about online ads and Web sites that use Oprah Winfrey's name to sell acai berry supplements as weight-loss miracles. Despite the warning, these ads are still common on Facebook and MySpace and link to fake blogs such as www.jennylosesweight.com that are designed to look like testimonials from women who lost weight on the acai supplements. Recent research by the Center for Science in the Public Interest identified more than 75 different phony blogs that led to Web sites touting acai-berry supplements as a weight-loss miracle.

THE FINE PRINT: The phony blogs link to Web sites that offer a free trial of an acai supplement, and while customers might think they only have to pay shipping, they could get billed as much as $87.13 every month if they don't cancel before the trial period ends. The fine print also explains that the trial period begins from the moment the customer orders the supplements, not after they receive the shipment.

BBB WARNS: Not only do health experts question the legitimacy of the weight-loss claims linked to the acai berry, BBB has received thousands of complaints from consumers against such acai supplement companies because many were billed despite never receiving their free trial or were billed every month despite numerous attempts to cancel.

THE PITCH: LEARN HOW I MAKE $67,000 A YEAR BEING A STAY-AT-HOME MOM

There are many ads on Facebook that advertise ways to make easy money from home. Similar to the acai berry ads, the ads link to blogs that were supposedly created by people who made money through a work-at-home program. One such blog written by a "Sarah Roberts" claims that she added "$67,000 a year to my family's income working 10 hours a week (that's over $128 an hour!)" by creating Web sites that are host to Google ads. Another, www.jasongetsrich.com, is ostensibly written by the newly married Jason, who makes "around $5,500 to $7,000 a month from Google."

THE FINE PRINT: The blogs direct readers to Web sites for programs such as Internet Money Machine and Easy Google Cash, where they can sign up for a seven-day trial access to information on how to make money from home. While the trial supposedly costs only $1.95-$2.95, the individual will be charged $69.90 every month if they don't cancel seven days from signing up.

BBB WARNS: In 2008 alone, BBB received more than 3,500 complaints from people who signed up for offers to learn how to work from home but were ultimately disappointed. Job hunters should also be aware that while some work-at-home opportunities have the word "Google" in their name and use Google's logo on their Web sites, they are not affiliated with Google.

THE PITCH: GET A FREE PURPLE [RED, PINK, GREEN, BLACK] MACBOOK.

Also common on Facebook are ads to get a free MacBook Air claiming that the company is seeking laptop testers. The ads lead to an incentive marketing program at www.colormyrewards.com, where participants must sign up for various products and services in order to earn their free laptop.

THE FINE PRINT: Customers must complete two options from each of the three tiers, Top, Prime and Premium, before receiving their "free" MacBook. Example; offers listed in the Top and Prime tiers include signing up for credit cards or trial offers for subscription services such as for vitamin supplements or DVD rental services. In some cases, the participant will need to pay for shipping, and if they aren't vigilant about canceling the trial offers they signed up for, they'll be billed every month.

Examples of the Premium offers listed on the Web site that must be met in order to get the MacBook include paying as much as $1,500 for furniture or purchasing a travel package with a minimum value of $899 per person.

BBB WARNS: Incentive programs can be extremely costly in the long run, and the fine print shows that the customer might have to pay a significant amount of money in order to get "free" items. And Apple does not even make MacBook Air in purple, red, pink, or green.

KELVIN COLLINS IS THE PRESIDENT/CEO OF Better Business Bureau of Central Georgia & the CSRA Inc. Refer questions or complaints about a company or charity directly to the BBB at (800) 763-4222, www.bbb.org or by e-mail to info@centralgeorgia.bbb.org or info@csra.bbb.org.