There’s a number of useful links and resources that you can check out on the topic of aesthetics and philosophy, including:

Derek Matravers on Art — Philosophy Bites — an excellent interview with an author of a number of books on aesthetics and the philosophy of art, looking at what defines the subject.

Various Online Philosophical Resources — The History of Aesthetics — here’s a number of original and annotated resources, collated by Theodore Gracyk

University of Oxford — Lecture series on Aesthetics and the Philosophy of Art delivered by James Grant

The meaning of art as viewed by various philosophers: Tolstoy, Hegel, Wittgenstein, Maritain

And a number of discussions for comparison:

What is Philosophy of Art? Richard Lee

What is art? Philosophy Talk

What Do We Really Mean By Art? By Marilina Maraviglia