Most MP3 players will convert MP3 to WAV. With Winamp, press CTL-P to bring up Preferences, From there, select Output in the left hand window, then select Nullsoft Disk Writer Plug-In in the left window. Press the Configure button to choose which directory you want your WAV files saved in. After you do this, every time you "play" a file in Winamp, it will actually be output to a WAV file in your chosen directory. To go back to actually playing files, bring Preferences up again, and select Output and Nullsoft Wave Out plug-in, which is your normal sound playing output plug-in. If you're using something other than Winamp, check the menus and look for "Options" or "Preferences".