Methods for operating multimedia computers to provide e-commerce voice communication capability directly between any computer connected to a computer network such as the Internet and any telephone device connected to the PSTN are disclosed. A simple click and call method is enabled by employing call interface software and the standard communication protocol over the network. The e-commerce voice communication system (EVCS) represented by an e-commerce voice communication symbol on a web page which, upon clicking, launches the call interface program, initiates a real-time communication channel between the client computer and the receiving computer, dials the desired telephone number via a voice modem. The EVCS method receives packets of voice data from the client computer, reassembles the packets of voice data into a stream of digital voice data, converts it to a stream of analog voice data, outputs the analog voice data to the voice modem, and outputs the analog voice data from the voice modem to the telephone line and vice versa from the telephone line to the client computer.