Adding album art to mp3 files

We have seen mp3 files without album art in our iPods,mobiles. It is quite ulgy to see the mp3s with default art. I searched many days to resolve this problem. All sites have same answer "download softwares for adding album art" . Recently I found that using windows media player we can add album art. Just follow these instructions to add album art in windows media player.
 1. Copy the picture(.jpg would be better) you want put as album art

 2. Browse your desired mp3 through media player .

 3.Right click mp3 file, you'll find an option " paste as album art" .
    Just click on the option and see the magic happens.