There's currently an ontology of music reading group going on at Leeds which I've been enjoying lots, as I've been interested in the ontology of art for a while now, but hadn't been able to motivate myself into getting to know the literature.
Anyway, it seemed to me that the kind of meta-ontological position I defend in my 'Truthmakers and Ontological Commitment' also had interesting applications to the ontology of music debate. So I've written them up. The draft is here. It's still rough, and I'm still in the process of getting acquainted with the literature, so comments are very welcome, but please be gentle with me!