Unless you feel comfortable following the Flexible Method for adding your own streaming audio files, this method must be set up for you. Also, this method only enables you to have one streaming audio file at a time on your site (unless you request a larger pre-set number of streaming audio files).
1) Create your Real Audio file and name it talk.ra (all lower case)
2) Log into Mainspring
3) Find the page called Audio, located under Orphan Pages.
4) Click "Documents" for the Audio page.
5) Click Edit for the file called talk.ra ...what you're going to do is replace the current file with another one of the same name.
6) Click Browse, find the talk.ra file on your computer and upload it.
7) Click Update Document - if the audio file is large, this can take a VERY long time. Don't touch anything until the screen titled "Manage Documents for Audio" appears, otherwise your new document won't be uploaded.