While Google dominates the online search market, the traditional Yellow Pages business has been shifted to online as well. Its online revenue, especially among those who remember when it was the main tool for phone searches, is growing, eMarketer reported.

More than six out of 10 U.S. Internet Yellow Pages (IYP) users were female, according to the latest 2007 full-year comScore data produced for the Yellow Pages Association (YPA).

Almost 90 percent of users were between age 25 to 64, disproportionate to their numbers among the general population, according to the study. Younger users, however, would rather choose other sources for most of their searches.

In addition, the Web Yellow Pages were preferred by many small businesses, and local online ad revenue has been growing in the double-digits every year since 1992, according to Borrell Associates, eMarketer reported.

"Online usage through IYP and local search is growing," Rod Diefendorf, vice president at Idearc Media, said in a statement.