NOTE: We do not want any MP3 files. We do not want to deal with any patent licensing issues required to encode and to stream the .MP3 file format. You can record yourself to standard .WAV file format and send that to us on a CD or DVD. We can encode it for you. If you want to have a hand at encoding yourself, then the file format we prefer is .ogg (Ogg Vorbis). It is FREE! and open source.
NOTE 2: If you can provide us a license to encode and distribute MP3 file format we'd be interested in your help.