There are a couple songs on the D2:ED website's media page ('main theme' and 'track 1'). After playing them in your browser, you should be able to copy the (randomly named) mp3 files out of your browser's cache folder (that's what I did in Opera, anyway: 'main theme' is 3,612 KB and 'track 1' is 2,457 KB).

Other than that, I don't know if someone has found an easy way to extract the music. see the music of div 2

Hopefully the English release will have a special edition including the full soundtrack, or it will be available separately.