I give here a sample of the types of applications that you likely want if you have a sound card under Linux. You can check the Linux Software Map, Internet archive sites, and/or files on your Linux CD-ROM for more up to date information.
As a minimum, you will likely want to obtain the following sound applications:
There are text-based as well as GUI-based versions of most of these tools. There are also some more esoteric applications (e.g. speech synthesis and recognition) that you may wish to try.