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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Re-locate files of selected tracks to new folder, preserve track meta-data
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Set year of selected tracks to their release date's year (if available)
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Copy Artist to Album Artist of selected tracks
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Remove iTunes tracks disassociated from files
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Open the iTunes Media folder in the Finder