Free web service to add music to a photo online for free. Add a background/cover photo to a MP3 song, put music to a JPEG picture, convert an image to a video with music online, add audio to an image. Select the image file, then select the MP3 file and click the "Create Video" button. Can take some time depending on the duration of the MP3 audio file.
Royalty free music by Bensound.com
I have recently found this awesome website that provides good music that can be used for free: Bensound.com