A system that enables a calling party to communicate with a called party over a communications network comprises: (a) a web page storage device that is operable to send, over the internet, (i) web pages to a calling party device, the web pages including a data entry screen into which a user enters a required telephone number or VoIP user name with which communication is sought and (ii) a call-in number; (b) a conversion device that is operable to receive over the internet, from the calling party device, the telephone number or VoIP user name and can cause the altering of call forwarding settings at a switch, such that a call from the calling party device to a call-in number will be automatically forwarded to a device associated with the telephone number or VoIP user name; (c) a dynamic line assignment module that can dynamically assign the call-in number.