While producing an E-learning content or web based training, a major decision making factor is whether to use audio for the benefit of the end users.
Generally, narration is used for this kind of Audio E-learning. Music and sound effects are rarely used. This article describes the technical background for producing the best quality audio for this purpose.
There are many factors that help determine the budget you should have for your project. They include lenght of the recording, purpose of the recording and the voice talents you choose. Sometimes you will even need mastered files so you can just send them to TV stations or stream them in the internet.