I recently bought a song from this site. If you have a PayPal account and can avoid iTunes, this site is a good option.
They do not have a huge library yet, but I recommend this site for those looking to download OPM music (I downloaded a Rivermaya song)
The prices are in PHP so downloading from this site is fast and convenient. Some songs also have lower prices compared to the ones sold at iTunes.
Support OPM 😀