Improved techniques for enhancing, associating, and linking various sources of metadata for music files, to allow integration of commercially generated metadata with user-entered metadata, and to ensure that metadata provided to the user is of the highest quality and accuracy available, even when the metadata comes from disparate sources having different levels of credibility. The invention further provides improved techniques for identifying approximate matches when querying metadata databases, and also provides improved techniques for accepting user submissions of metadata, for categorizing user submissions according to relative credibility, and for integrating user submissions with existing metadata.