Download Vsound
From the site:
This program allows you to record the output of any standard OSS program (one that uses /dev/dsp for sound) without having to modify or recompile the program. It uses the same idea as the esddsp wrapper from the Enlightened Sound Daemon (in fact, vsound is based on esddsp). That is, it preloads a library that intercepts calls to open /dev/dsp, and instead returns a handle to a normal file. It also intercepts ioctl’s on that file handle and logs them, to help convert the audio data from its raw form. Vsound then uses sox to convert the raw data to the desired file format.