If the sound file is very short, you could include the transcript in the alt-text of an image that accompanies the link to the sound file, e.g.
Listen to a message from the author.
<IMG SRC="audio.gif" ALT="Sound file: Let's work together for accessibility. ">
Listen to a message from the author. </A>
If the audio file contains lots of information, then you might want to link to a file that contains a complete transcript:
Let's listen to an excerpt from "The Walrus and the Carpenter," by Lewis Carroll.
To Checkpoints for Guideline 1.
Audio transcript: Excerpt from "The Walrus and the Carpenter," by Lewis Carroll.
"The time has come," the Walrus said,
"To talk of many things:
Of shoes-- and ships-- and sealing-wax--
Of cabbages-- and kings--
And why the sea is boiling hot--
And whether pigs have wings."
Next slide: Example for Checkpoint 1.1m