iAlbumArt allows you to quickly and easily download album cover artwork for your entire iTunes music library. You can even update albums that are already on your iPod.
iAlbumArt works by searching Amazon's music database using the album and artist information from iTunes to locate and download the artwork. You can also manually pick the version of the art you want to save. The artwork is saved in the ID3 tag of each track as a compressed image (PNG).
iAlbumArt works and feels like iTunes. You pick the iTunes play list you want to use and iAlbumArt will show you the current artwork and allow you to download covers manually or in batch. Cover art is saved to the individual audio files. You can even update the artwork for tracks on your iPod. Just select iPod from the playlist.