This plug-in can be used to convert most output formats to MP3. You can use it just like you use the WAV writer that is included with Winamp, only this one writes to MP3. This plug-in requires the proper MP3 ACM codec to be installed on your system.
To output a playlist of files to MP3, open Winamp, load the playlist of files, and turn off shuffle and repeat. Then, open the preferences (CTRL+P), go to the Plugins/Output section, and select "Nullsoft MP3 Output" as the new output Plug-in. Hit configure to select the MP3 format to use. If the plug-in complains that the proper ACM codec is not installed, then you need to get
the codec (see below). If the configuration of the format is not successful, switch the output plug-in back to the default (Nullsoft waveOut).
Close the preferences, hit play, and sit back while it reencodes. When you"re done encoding, open the preferences and switch the output plug-in back to the previous setting (usually Nullsoft waveOut).
P.S. You must deactivate any DSP plugin before encode mp3"s. You can get LAME ACM Codec from HERE P.S. You must deactivate any DSP plugin before encode mp3"s