Google - Where can I find a midi form or piano sheet music of "Wings of Faith” from Soul Calibur?

There are various ways. The music will be encoded somehow and MIDI isn't a bad bet given that soundcards can play MIDI. Although it could also be MP3, given how much space is available to developers these days.

You could write to Namco and see if they'd let you have it on the proviso you don't distribute it.

Finally, I know this sounds fantastical but it is actually possible now to reverse engineer a MIDI file from a sound file. I've done it myself. The results weren't perfect, of course, but they were better than expected.

Failing all that, you (or someone else musical) could do it, given time. Or you could Google it. I found something promising but it was on a malware site so I didn't open the page.