For decades, direct-marketing and mail-order companies have built, bought and sold those lists -- organized by region, age, income, and buying habits -- in order to better target us with sales pitches.
Now, as 60 Minutes Correspondent Lesley Stahl reports, direct marketers are moving their lists onto a powerful new medium: the Internet.
At the recent direct marketing association trade show in Toronto, saleswoman Olivia Duane demonstrated a new product that maps the demographic makeup of any neighborhood in America -- street by street, almost house by house.
"We can look at education, ethnicity, home value, occupation," Duane explains. "We can see an incredible level of detail."
A computer shows detail of a very small section of Chicago. Let's say a business wanted to mail a sales offer just to Hispanics. Sign onto the Web site, click the mouse a few times, and the changing map color shows just how many Hispanics live there. Put in other criteria and the map changes again.
"Through the Internet I can now very easily go and say 'give me all the households with college grads, presence of female in the house,' etc." Duane says.
Direct marketers say technology like this will help them make their mailing lists more accurate and help make sure people don't get catalogs they don't want or offers they won't read. But consumer privacy advocates like Jason Catlett see it differently.
"So there's now a two-way information super-highway, between the offline world of tele-marketers, cataloguers and other physical sales people, and the Internet," says Catlett.
Catlett says much of the personal information for sale on the Internet comes from huge database warehouses -- companies like Acxiom and Experian -- that you've probably never heard of. But they've heard of you; each of those companies claims to have info on 95% of all American households -- where you live, what you drive, your buying habits and credit history.
"Companies have been gathering information about us for years. Insurance companies know a lot. Direct marketing firms know a lot. I get catalogues constantly; I don't know how they even know who I am. So I guess I'm asking, what's really new here?" Stahl asks Catlett.
"What's new is the speed with which this can be acquired," Catlett replies.
Talk about speed! At one Web site, www.my-prospects.com, businesses can buy a list of names and addresses in just a few seconds.
"So this illustrates the way that direct marketing database companies collect huge amounts of information about large numbers of people," Catlett explains. "And then they slice and dice and sell little bits of it to busineses based on whether they're interested in New York consumers, or Missouri consumers, or wherever."
At the site, businesses can either buy ready-made lists with catchy names like "big-spender parents," or create their own.
Catlett continues, "Household income -- you can select from $75,000 to $99,000. Head of household is aged 65 to 75. They definitely own their house. We want the phone number because we can telemarket to them. And we're gettingÂ… only paying an extra two cents -- that's the price of your phone number."
And with your phone number for sale on the Internet for two cents, you can expect to get a lot more phone calls during dinner.