When John R. Williams wanted to hire a nanny, he went to the Yellow Pages and found a service located near his home in Bethesda. After several interviews, he chose a woman he felt comfortable with and forked over $1,600 to the service.

He soon regretted his decision. "The woman was the antithesis of what she presented in the interview," Williams said.

After the service ignored several phone calls demanding his money back, Williams says, he gave up. What infuriated him most was the service's advertisements that stared at him from the Yellow Pages: "Voted best nanny practice," the tagline read. "That was always going through my mind," Williams said. "No one asked me for my vote."

You can read all about it on ILevel, a World Wide Web site that grew out of the experience. It offers "alternative dispute resolution" (www.ilevel.com) that Williams intends to help aggrieved customers work out disputes with companies. It might also be applied, he says, to help one company in a dispute with another.

Here's how it works: The customer sends a complaint to ILevel describing his or her version of the transaction, what went wrong, and what type of compensation or resolution the customer hopes to gain. ILevel then forwards the complaint to the vendor requesting a response. If the two parties do not reach a resolution within 30 days, ILevel posts the correspondence on its Web site.

That, of course, can be embarrassing for a company. No matter how extreme the claims against it may be, Williams figures he's protected against legal action because he isn't the one making the allegation.

With the correspondence in view, visitors to the site can vote for either vendor or customer by typing their opinion into a special box. The votes do not actually affect the process, but are more for entertainment, "Judge Judy" style. "The difference is you can judge for yourself," Williams said. After all, he noted, "how many people shout at the TV?"

Some of the few companies whose names have turned up on the new site see the service as biased in favor of consumers. While Williams describes his site as a "buyers community," he denies bias and points out that the site also has an area where people can rave about positive experiences.

In the meantime, he's puzzling out how he might make money from the site, which he now runs from the offices of another company he founded, electronic publishing firm ProInfo in Washington. ProInfo's 10 employees divide their time between ProInfo and ILevel.

So far, he has not charged anyone. He hopes to build a large following on the site and eventually charge a membership fee, for customers and companies alike.

Williams is not the only one seeking money in solving what he calls "the oldest complaint: `I didn't get my money's worth.' "

"We're going to see lots and lots of experimentation," said Ethan Katsh, professor at Amherst University and director of a service called the Online Ombuds Office. Funded by nonprofit groups, it takes complaints online at http://aaron.sbs.umass.edu/ center/ombuds/default and works on finding resolutions.

In March, online auction service eBay Inc. agreed to set up an area on its site for customers to log complaints about the service or its users. The area was linked to Amherst's Online Ombuds Office, where the staff reviews the complaints and attempts to mediate between the parties. Katsh said the university is negotiating with eBay to continue offering its services, which would be paid for by eBay.

Williams said he may consider trying to offer his services through a third party, such as financial institutions. For example, banks could offer the service as an inducement to people to open checking and savings accounts. Or, he said, perhaps companies could offer the service as an extension of their customer service arm.

"The question we've given a lot of thought to is how do you provide a service in situations where the service really costs more than the value of the transaction" that's in dispute, Katsh said.

For example, one ILevel user who complained about BMW asked only for $57 in compensation.

Williams said he has had some success in getting results for angry customers. However, some vendors claim he is doing little more than allowing people to vent and leans toward the customer's version of events.

For example, the BMW complaint, submitted by Washington attorney Hank Schlosberg, states he had to have a fog lamp fixed after it fell off his new car -- twice. The first time, the BMW dealer did not charge him. The second time, he said, the dealer refused, telling him he was at fault.

After several back and forths with BMW, both ILevel and Schlosberg were told the company supported its dealer.

On the ILevel site, Williams has classified the dispute as "not resolved." But "in our mind it's been resolved," said Martha McKinley, spokeswoman for BMW of North America Inc. in Woodcliff Lake, N.J. "We have reviewed the file and we have paid some attention to this, but we feel that compensation for the expense he paid . . . is not in order here."

Another company whose name has shown up on the site, Zomax Inc., said it did not receive any help in terms of mediation.

"This is a strange situation," said the company's attorney, David R. Marshall of Fredrikson & Byron P.A. in Minneapolis. "We received this notice out of nowhere and responded . . . and that was that. We did not enlist their help and they did not provide any service whatsoever in resolving anything."

Williams admitted he has a long way to go before he is operating smoothly. For one thing, he said he will need to figure out "how can we handle 10,000 complaints without burping."

That problem seems a bit far off: As of now, there are only 15 complaints posted, although he is working on many others, he said. Already, though, he has had myriad problems, such as companies that turn out to be ghost operations -- he has a stack of letters marked "returned."

Still, Williams said, "I'm just keeping my head down and moving toward [my] vision." The end result, he said, will be to build a community of informed buyers, "not a whole lot different than being at a cocktail party telling horror stories about getting your car fixed."

CAPTION: John R. Williams founded ILevel after a bad experience hiring a nanny. He hopes to build a following and eventually charge a membership fee.