Choose a music file on your computer that would like to add your live voice to. The music can be from a CD, MP3, MP4 or WMA file, as long as it is playable on your computer.
Connect a microphone to your computer so that you can record audio input. If you want a high-quality recording, you should use a high quality USB microphone such as those used by voice-over talent. USB microphones can be purchased from your local computer retailer for $20 to $40, depending on the brand.
Cue your music to the point you would like to begin recording your voice.
Open your sound recording software program. If you are running Windows Vista, you have the option of using the built-in sound recorder by clicking on your Windows "Start" button and performing a search for "Sound Recorder." You can also compare and download free sound-recording software by clicking on the link in the "Resources" section of this article.
Begin playing your music. Click on the "Record" button in your sound-recording software program. Press the "Stop" button when you are finished recording.
Listen to your recording by pressing the "Playback" option. If you are satisfied with the recording, save it by selecting "File" and "Save As."