It enables easy and quick searching and delivery of information desired by a user based upon a portion of time-series data which consists of clip information from music, a movie, a commercial message, or the like. The user accesses an information search server from a user terminal which is connected to a network, and, using this portion of time-series data as a search key, performs searches upon said server for information related to the time-series data. The information search server returns the name of the tune, the title of the movie, the name of goods advertised in the commercial message or the like to the user terminal via said network as search results, and the search provider levies a price for said search from the user.