A database search method and system utilize user community defined facets and facet values for refining searches. The system provides access to a database having a plurality of records in respective categories of information. Each record has one or more facets to the respective category of information. The system enables user input of a search term formed of a first parameter indicative of at least one category of information of the database. In response to the user input, the invention system displays (a) a set of search results, including records from the database of the at least one category of information, and (b) a listing of facets and/or facet values of the records in the search results. The listing of facets and/or facet values serve as suggested additional parameters for further refining the search terms or guiding user navigation of the database. In response to user selection of a facet value from the listing, the system refines the search term resulting in a refined search term formed of the first parameter plus the user selected facet and/or facet value. A search of the database is rerun using the refined search term. The facets and facet values are defined by a computer network community of users over time and through use of the network community portal. Another embodiment is an advertising engine that displays targeted advertisements to the user based on refined search. Another embodiment is a method that utilizes refined search to help the user with navigation of a site (e.g., website or other computer network site) as a component of a GUI.