Hi, there. I am using Audacity 2.0.5, installed via .exe, to record Skype calls. I have a Plantronics USB headset with attached mike.
I get very good recording and sound levels from my mike, but the person on the other end, usually speaking from a telephone landline, is way too faint on the recording. (The other person’s voice sounds fine in my headset.)
I don’t see anything in the preferences menu that would help, and I’m not finding anything in the manual or my tutorial. Thanks for your help! 
That’s because there is no help. What you are recording is the acoustic leakage through your headset and onto the recording. If everything was perfect, that voice would go away, not get louder.
Windows people can try Skype Call Recorder, or for really good control over your production voices, Pamela Professional or Pamela Business.
http://www.pamela.biz/en/products/
If you reeeeely need to rescue your present show, you might try Chris’s Compressor.
http://theaudacitytopodcast.com/chriss-dynamic-compressor-plugin-for-audacity/
Chris is an intelligent volume manager and can handle different voice levels within one performance much better than “blind” compressors.
Koz
oh, that’s too bad. I love audacity. I have used Skype Recorder in the past and found it buggy; then, it didn’t work for a while when Microsoft changed things. I’ll have a look at Pamela. Thanks for responding.
Pamela is the gold standard. The lower two licenses have restrictions. The upper two paid licenses have no restrictions you’re likely to run into. You can try it and see if it does what you want. The only complaint I know about is a user who wanted separate tracks for Far and Near, but missed a preference setting and got a single mixed track instead. You’re stuck once you do that. You can’t split a mixed performance into individual actors.
Koz
Audacity can’t record Skype because Skype is two sources, your mic and the other person.
There is no decent workaround to using Audacity to record Skype with a USB headset.
Gale
There is another solution, [Moderator edit] vEmotion Gold ($39.95 US) [End of Moderator edit] can record Skype both ways and from other sources, perfectly.
Enjoy it
[Moderator note:]There are many non-free commercial products available. Users should do their own research before buying one.
Skype Call Recorder is a free open source Skype call recorder. It is reported to work well on both Linux and Windows (I have used it on Linux).
There used to be a free product from The Conversation Network called Levelator. It was designed for use on podcasts where multiple people were being recorded using multiple microphones, and it did a very good job leveling out the audio from different speakers. Although it is no longer being supported or developed, it is still available for download.
http://web.archive.org/web/20130729204551id_/http://www.conversationsnetwork.org/levelator/