I was hoping someone would ask that. Remember fiverr.com, the Mechanical Turk for people with talent, where every task is priced at $5? Somebody was offering to record a phone tree. I paid her $5 for half the job, liked what I got, paid her $5 for the other half, then got her email for ongoing work at a more appropriate wage.

God, I love the Internet.

Incidentally, the total cost of getting this project this far has been about $450, including $250 put on deposit for Twilio. (Better to have too much than too little, right?)

I'm not sure what was used here, but I've used Voices.com before to source voice overs and have been really happy with it. Worth a look if you need something like that.