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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Convert selected tracks and export the converted files to a new folder
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Recreate a playlist such that its visible columns mirror the Music library
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Export artwork of selected tracks to parent or specified folder
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Exports and then re-imports selected tracks' artwork
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Apply selected CD's CD Text to its disc and track tags
downloaded 43m 34s ago
Create a Ringtone track from a selected track