OS X 10.10 or later. This script will look for an image file in the parent folder of each selected track's file--presumably its Album folder in which you have previously placed an image file of some sort--and apply the data from that image file as artwork for the track.
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Two scripts copy text from clipboard to current or single selected track's lyrics tag
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Display, create text file listing info of dead tracks
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Copy Artist to Album Artist of selected tracks
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Gather audio tracks whose files contain no artwork metadata
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Rename selected tracks' Song Names with their filenames (minus extension)
downloaded 1h 29m 35s ago
Sort purchased tracks into discrete playlists by name or Apple ID