(MONEY Magazine) – Think, for a moment, about how you make important buying decisions. Say you're in the market for a new camera, or a car, or--as in my case--a cell phone. Without the Internet, you might be lucky enough to stumble across a magazine or newspaper article full of expert opinion at exactly the right time. The fact is, that seldom happens. So maybe you'd seek advice from friends and family; they, however, are rarely able to answer tough questions like, say, whether lithium ion batteries significantly extend the talk time of the new Nokia 6190. In the end, you'd probably end up relying on a salesperson who might or might not be knowledgeable and might even have a hidden agenda. In short, such decisions have never been easy.

The Internet is supposed to have helped change that, but I feel it's fallen short of its promise--at least so far. Retail sites and manufacturers offer plenty of product specifications but little objective advice. And while there are a number of product-specific review sites--like CNet for computers--useful, unbiased advice is still tough to find.

Now along comes a wave of "online community" sites like ConsumerReview.com, Deja.com and Epinions.com, where consumers share their experiences with various products and services, from electronics and cars to online brokers and cruise lines. Some of these sites are sprinkled with expert advice as well, but their selling point is the pooling of public opinion--not the pronouncements of a few cloistered pundits, but the collective wisdom of real-life users, the people who live with the products day in and day out.

It's a great idea, of course, and another example of the Internet putting power in the hands of the consumer. Nevertheless, I initially felt skeptical. After all, aren't the experiences of individual consumers, who rarely have a comprehensive view of an entire product category, inherently limited? Since I happened to be in the market for a cell phone and service, I set out to learn for myself what the online communities had to offer.

My first stop actually wasn't an online community but a site called Point.com, which compares cellular plans available in your area and the phones themselves, side by side. After a little research, I found myself intrigued by the Samsung SCH-3500 because of its voice-activated dialing and ability to access the Internet. Since there were no reviews available, I headed to what's probably the hottest of the new consumer opinion sites, www.epinions.com. Among the consumer-penned commentaries on dozens of subjects--even Oprah's Book Club selections--I found nine recent reviews of the $150 Samsung cell phone, including 1,300 words by someone named "maxntropy," who was particularly impressed with the phone's speech-recognition capabilities. "It really works!" he gushed. "Even while driving at warp speed with the stereo on quite loudly." Clearly not just a shill for Samsung, he was less satisfied with the base charger: "It is very difficult to slide the phone in and get it charging...it has to slide in just right."

Turns out this thoughtful review wasn't an anomaly. In fact, I found Epinions.com to be the best overall source for detailed consumer opinion, perhaps as a result of the site's innovative strategy of paying people for their opinions. Sure, this policy inspires some worthless babble, but because the payments are so small--between 1[cents] and 3[cents] each time an opinion is read--the only way writers can make any real money is to pen useful comments that earn them the label of "trusted" reviewer. Trustworthiness also entails being open about yourself--listing your profession and hobbies and even posting a photo. (I learned, for example, that "maxntropy" is a thirtysomething market strategist from Birmingham, Mich. with an interest in science fiction, public policy and nanotechnology, and that he sports a little tuft of hair, or "soul patch," beneath his lower lip.)

I'm not sure what kind of business model this all makes for--paying every Tom, Dick and Harry for his opinions may be a strategy only an Internet entrepreneur could love. As an incentive for thoughtful, honest and even clever reviews, however, it seems to work. Maybe that's why I found Productopia (www.productopia.com), a product-review site that's been generating some buzz, considerably less helpful. Perhaps because it doesn't pay for opinions, I didn't find a single consumer review of the Samsung phone. As for the site's prominently featured staff reviews, I found that the Samsung blurb read more like ad copy than objective advice.

I still wasn't ready to buy. One thing that neither Epinions.com nor Productopia provided me with was a ranking of products against similar items. For that, I had to check two other sites: www .deja.com and www.consumerreview .com, both of which rate the relative popularity of products based on consumer reviews. This makes these sites good places to begin if you don't have a particular model in mind. The Samsung, it turned out, was No. 2 on Deja but wasn't mentioned at ConsumerReview.

Of these two sites, Deja.com has more to offer--at least for now. Its consumer reviews tend to be short on detail but plentiful. I found 32 comments, among them this testimonial: "I have had eight different phones over the years, and this tops the list. The battery life and size are the best." Not terribly expansive--although the chance to hear from someone who's used that many models in the real world is exactly what you'd hope for from this kind of site. I was becoming less skeptical.

Deja.com's best feature, however, may be its ability to scour tens of thousands of Internet newsgroups for information specific to your region. I wanted to know how cellular carriers fared on the Northern California roads that I frequent, so I typed "cellular," "highway," and "Tahoe" into the site's search engine and found one November posting about AT&T's cellular coverage on Highway 50 south of Lake Tahoe. "Once you get past Placerville, you'll notice that the digital service is gone, and there are huge areas of 'no service'...once you cross Echo Summit, you get great coverage." That's the kind of insight experts rarely offer.

Little doubt remained--either about the quality of the phone or about whether these sites offer worthwhile advice. The minor criticisms of the Samsung phone were far outweighed by the chorus of positive and well-reasoned remarks. As for the online communities, even though I expect I'll still seek expert reviews and look to friends and family for advice, these sites are invaluable complements. There are still product categories with next to no worthwhile discussion. But as more people discover and add thoughtful opinions to these sites, they'll no doubt become an essential tool for consumers trying to make the right call.

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