24. The apparatus of claim 20 , wherein when the data of interest includes data of interest from at least two web sites of the plurality of web sites, the data of interest from the at least two web sites is extracted.
20. An apparatus for extracting information of interest from at least one web site of a plurality of web sites, the apparatus comprising: (A) for each respective web site W in the plurality of web sites, (i) means for creating a respective description of data of interest that identifies the web site W; (ii) means for developing an extraction pattern from a web page output from the respective web site W using a graphical user interface tool, the extraction pattern being adapted to extract data from a plurality of web pages of the web site, wherein the extraction pattern comprises a regular expression; and (iii) means for associating the developed extraction pattern with the respective description of data of interest for the respective web site W; (B) means for receiving a value for use as an extraction parameter in the developed extraction patterns; and (C) means for obtaining said data of interest by querying the at least one web site of the plurality of web sites using the value and the developed extraction patterns associated with the respective descriptions of data of interest; and (D) means for extracting said data of interest from the at least one web site of the plurality of web sites and storing said extracted data of interest.