1. A computer-implemented method, comprising: collecting search activity data of search engine users, wherein the search activity data is descriptive of searches performed by said users on each of a plurality of index-type search engines, wherein each of the plurality of index-type search engines maintains its own proprietary index obtained by crawling web sites for building a unique database for generating search results, wherein each of the search engine users interacts with a search results page of the index-type search engine to view search results; for a particular search destination, programmatically analyzing the collected search activity data by a computer system having a processor and memory to identify a plurality of search events in which a search engine user selected the particular search destination from a search result set to access the destination; and for each of the plurality of search events, identifying from the collected search activity data, and recording in computer storage, at least the following information: (a) the search engine used, (b) the search query submitted, and (c) a position at which the destination was listed in the search result set.