1. A computerized method for estimating coverage of search engines, each search engine maintaining an index of words of pages located at specific address in a network, comprising the steps of: generating a random query, the random query being a logical combination of words found in a training set of the pages; submitting the random query to a first search engine; receiving a set of URLs in response to the random query; randomly selecting a particular URL identifying a sample page; generating a strong query for the sample page; submitting the strong query to a second search engine; and comparing result information received in response to the strong query to determine if the second search engine has indexed the sample page.