OS X 10.8 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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Write size of track's artwork to chosen tag or copy tracks with artwork of certain size to playlist
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Resample selected tracks' artwork to user-set size limit
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Displays files in iTunes Media folder not in iTunes track library
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Display, create text file listing info of dead tracks
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Drag-and-drop to convert audio files with iTunes
downloaded 8m 52s ago
Locates pairs of track entries pointing to the same file