Read the title. They're asking how to move the mp3s from the soundtrack disc. There ARE mp3s on the OST, just that unless you read Japanese it can be pretty hard to figure out.

If you have a Blu-ray player on your PC, you can just copy the files over after you run the disk. If you're using the disc in a ps3 or other device, make sure its wireless enabled. First go to "Extras" in the Blu-ray disc menu, then "MP3 Download". It'll give you a link looking like 192.168.x.x. Type that into your browser on your pc, and it should give you the links from the disc to download the mp3s to your PC. I can explain more detail if you need. ;3