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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downloaded 25s ago
Rename selected tracks' Song Names with their filenames (minus extension)
downloaded 48s ago
Set choice of various number tags of selected tracks incrementally
downloaded 7m 16s ago
Remove iTunes tracks disassociated from files
downloaded 11m 0s ago
Apply selected CD's CD Text to its disc and track tags
downloaded 15m 45s ago
Perform search-and-replace on text in your choice of tags
downloaded 16m 40s ago
Resample selected tracks' artwork to user-set size limit