Sep Update: Album Extract 2018 being discontinued. Please down 2019 version instead.
Album Extract EX is a small tool that allows you to fetch missing covers for your music. If you have a huge library of music, this could be the right tool for you.
The program supports many services such as iTunes, Google Play Music, Last.FM and many other sources for fetching album covers for your music.
With the auto detection feature, you can find and cover quickly.