This is NOT the kind of LAME we're talking about, but I thought you might chuckle at the thought. I know I did when I first heard I was going to have to using something called LAME to make Audacity work the way I wanted it to.
LAME is the MP3 converter tool you are going to need to make Audacity do what Audible wants it to do. Remember, when you upload files for review by an author, they must be in the MP3 format. For various reasons too painful to go into in this blog, you will need a tool to make Audacity recordings into MP3 recordings.
So, what is LAME? It's a tool that's been around since 1998 created by a member of the audio production community. Think of it like a little app that does what you need done.
Can you trust it? YES. I've been using LAME for several years with Audacity. It's not going to give your computer a virus. It's actually a quite small little add-on that you can download here: http://lame.buanzo.org/. If that site looks scary, then go back to Audacity's site and let them redirect you to the converter from their own pages (it's going to be the same place).
Still worried about downloading it?
You can go through Audacity to get the link at http://manual.audacityteam.org/man/faq_installation_and_plug_ins.html. Don't worry, it won't hurt my feelings if you don't trust my links. Do it the safe way.
Once you get it, you can convert your recordings into the most holy, revered MP3 format. How? It's easy.
1. Record your audio file.
2. Under File>Export Audio.
3. Select MP3 as the format.
4. Congratulations-- you are now an MP3-enabled Audacity user!