How do you change a song file from .zip to .mp3?? Its urgent

You unzip it

Is that supposed to be funny or something.. Because its seriously not.

Wasn't meant as a joke.
Zip files are an ARCHIVE that contains other files.
If you are running windows XP or above, simply double click and it will open.

I'm sorry, but maybe I just over estimated your knowledge. Since you seem to understand what an MP3 is, I just assumed you would know what a ZIP is. The ZIP file format has been around since the old DOS days. It is so much of a standard that Microsoft built in support for ZIP files with Windows. So all you need to do is Open the file and "Extract" the files it contains.

According to what you wrote I am assuming that you might have changed the extension of the file so just change it back to .mp3 or if u have zippd it then just extract the mp3 file from the zipped file.