1. A computer-implemented method comprising: a) accepting, with an advertising system including at least one computer, information defining at least one ad spot associated with at least one instance of an audio document; b) accepting, with the advertising system, offers to have advertisements served in the at least one ad spot; c) arbitrating, with the advertising system, among competing advertisements, using at least the offers, to determine at least one advertisement to be served in that at least one ad spot; d) transmitting, with the advertising system, the audio document for delivery to an end user client device; and e) transmitting, with the advertising system, the at least one advertisement to be served in that at least one ad spot, for delivery to the end user client device, wherein the act of arbitrating occurs after the act of transmitting the audio document has been initiated.
1. A computer-implemented method comprising: a) accepting, with an advertising system including at least one computer, information defining at least one ad spot associated with at least one instance of an audio document; b) accepting, with the advertising system, offers to have advertisements served in the at least one ad spot; c) arbitrating, with the advertising system, among competing advertisements, using at least the offers, to determine at least one advertisement to be served in that at least one ad spot; d) transmitting, with the advertising system, the audio document for delivery to an end user client device; and e) transmitting, with the advertising system, the at least one advertisement to be served in that at least one ad spot, for delivery to the end user client device, wherein the act of arbitrating occurs after the act of transmitting the audio document has been initiated. 3. The computer-implemented method of claim 1 wherein the audio document includes a live Dr recorded musical work with lyrics.