AUCKLAND, New Zealand — The most frequently asked question wine writers everywhere receive (apart from the perennial “How can I get a job like yours?”) is: “Where can I find the wines you recommend?” The person who has the answer resides in, of all places, Auckland.

“It always bothered me that there was no simple, easy way to find out which wine merchant has which wines,” the creator and developer of the Web site Wine-Searcher.com, Martin Brown, 50, said during a recent interview.

Although he was born and raised in New Zealand, Mr. Brown only returned to that country this past February after spending 20 years in London working for various English wine companies, such as the venerable Berry Brothers & Rudd, as an information technology specialist. “I’m really more of a computer geek than a wine geek,” he said.

Although Wine-Searcher.comis still largely unknown among everyday wine shoppers, it is the secret agent of avid wine buyers trawling for either the best price or a hard-to-find producer or vintage. What’s more, it casts a wide net, encompassing wine merchants around the world.

“I started it in1999 when I was still working for Berry Brothers,” Mr. Brown said. “I developed some proprietary software during my off hours and I began with just seven merchants. I have to say that it was originally meant for the wine trade rather than consumers, so that competing merchants could see what others were charging for the same wine.”

That focus changed rapidly as Mr. Brown acquired ever more wine inventory listings from merchants around the globe. “It’s all about completeness, you see,” he said. “The great challenge is to try to get every wine merchant I possibly can, in every country possible. Of course, you can’t really do that, but that’s the goal.”

Mr. Brown has come closer to his idealized goal than anyone else. Although Wine-Searcher.com has competitors, such as Winezap.com and Wineaccess.com, neither is anywhere nearly as extensive. Wine-Searcher.com lists 8,500 merchants around the world, according to Mr. Brown.

The Web site works simply enough from the user side. You type in the wine you’re looking for. You can add the vintage, or leave it out of the search. A drop-down list gives you the option of choosing merchants only in one particular nation, alphabetically from Argentina to Venezuela, or in the case of America, nationwide or by individual state. You can also choose the currency in which you want the wine price quoted.

Let’s say you’re looking for a special bottle from a particular vintage as a birthday gift, from the year the recipient was born. You choose, say, Château Latour with the merchant source as “All Countries.” You purposely leave the vintage date box blank to see which vintages are available. You click on “search” and up pops a list of 103 vintages of Château Latour, from 1848 to 2006.

After you decide which wine you wish to buy, you click on the link, which redirects you to the merchant’s Web site. After that, you’re on your own, as you deal directly with the merchant. Wine-Searcher’s cost to you: Nothing. And the cost to the merchant? They also pay nothing.

So how does Mr. Brown make his money? Banner advertising from 300 to 400 merchants, he explained.

The other revenue source comes from $29.95 annual subscriptions to the more complete listings available under what’s called Wine-Searcher Pro. For example, the free portion of the site notes that it will show only 50 of the 71 merchants offering the aforementioned 1961 Château Latour. With Wine-Searcher Pro, you can also further refine your search by indicating the bottle size you’re seeking (from half-bottles to double-magnums to case lots only), and see the price history of the wine from current prices to those fetched only a month ago, or as long as four years ago.

“We have 10,000 who pay for the pro version,” Mr. Brown said. “And we have about 500,000 users who don’t pay anything. About 55% of those who do pay, by the way, are in the United States.” Americans, he says, are by far the largest users of Wine-Searcher.com.

One complaint voiced on Internet wine chat boards about Wine-Searcher is that merchants sometimes do not actually have the wine in stock. Upon hearing this, Mr. Brown sighs. “This is always a problem, I know,” he said. “But we work very hard to prevent that, if it’s at all possible. “The way we get our listings is that we download the data from a merchant’s Web site,” he continued. “For very big merchants such as Zachys, we download the data from their site every day. With others, we do it every three days. It takes about 14 hours to download all of the data for those every-third-day updates.”

What’s more, according to Mr. Brown, who employs a staff of six to run the Wine-Searcher site, “We do a ‘mystery shopper’ where we contact a merchant directly and inquire ‘Do you have this wine in stock right now?’ We drop about 20 merchants a month from Wine-Searcher because of the quality of their listings.”