Direct your Internet browser to an online conversion application site (see Resources section).
Upload the Windows media file to the conversion application. Most sites have a "Browse," "Upload a File," or "Upload" action for uploading files to the application.
Locate the Windows media file in the dialog box that opens. Select the file, and click the "Open" button to upload the file.
Look for a drop-down menu like "Convert file(s) to" or "Output Format," scroll through the available audio file formats in the list, and select "mp3."
If prompted, provide your email address. In this case, the application sends the converted Windows media file as an email attachment.
Select the "Convert" action to begin changing the Windows media file to an .mp3 file. After conversion, a redirect screen either indicates delivery of the new file to your email address or provides a download link.