This question kinda depends on what hardware/software you have, and I don't know of any pre-made scripts for doing this. I can refer you to the building blocks, though. If you have a consumer-grade voice modem, Modem::Vgetty is probably what you want. It can play prerecorded audio clips in a certain format onto the line, along with some other possibilities for interaction. If you are looking to generate audio for this purpose, check out the Festival modules for text-to-speech. I think there is also a tutorial or something about Modem::Vgetty, if you google it. Good Luck!