The present invention is a system for conducting commercial transactions over the Internet, whereby a shopper can simultaneously search for a plurality of items on at least one website with a single search command. The shopper can selectively specify the items of interest to be searched and can also specify and/or exclude websites to be searched. The system also searches a selectively alterable set of default website(s) and intelligently recommended website(s). Under one search command, the system simultaneously searches for all of the items on any combination of the following: site(s) specified by the user, a default website, an alterable set of default or intelligently recommended website(s). Information regarding the items retrieved as a result of the search is compiled under an alterable set of criteria, and displayed for viewing by the shopper. The shopper can simultaneously purchase selected ones of said items with one order command.