If you want to make money online selling iTunes products, then you might want to become an iTunes affiliate. They run the affiliate program via LinkShare. And, it’s available to residents of the US, Europe, Japan, and Australia.
The program offers a 5% commission to all qualified sales that are generated from your affiliate link.
Types of products that you can sell from iTunes: music, audio books, videos, podcasts, radio shows, TV shows, and iPhone applications.
For more info, check out the iTunes Affiliate FAQ page.