To grab from analog audio line-in or to convert raw CDDA audio from audio CD's you'll need one of the following.
Wavrec is distributed as part of wavplay, which can be downloaded from:-
ftp://sunsite.unc.edu/pub/Linux/apps/sound/players/
To convert CD audio data to WAV format, sometimes known as CD ripping:
http://metalab.unc.edu/pub/Linux/apps/sound/cdrom/
GramoFile is a computer program, running under the Linux operating system (and some other UNIX-like OSses -- and even DOS/Windows now!), with the main goal of putting the sound of for example gramophone records on CDs.
It is able to record hours of CD quality music, split long sound files in separate tracks, and remove ticks and pops from recordings.
http://panic.et.tudelft.nl/~costar/gramofile/
Cdparanoia is a Compact Disc Digital Audio (CDDA) extraction tool, commonly known on the net as a 'ripper'. The application is built on top of the Paranoia library, which is doing the real work (the Paranoia source is included in the cdparanoia source distribution). Like the original cdda2wav, cdparanoia package reads audio from the CDROM directly as data, with no analog step between, and writes the data to a file or pipe in WAV, AIFC or raw 16 bit linear PCM. Compared to cdda2wav, it's much slower but really gets the best results you can get even from CDs that are difficult to rip for scratches or other read-errors.
http://www.xiph.org/paranoia/index.html