Eternal Arcadia (as it's named in Japan) or Skies of Arcadia Original Sound Track was released back in October of 2000 and was composed by both Tatsuyuki Maeda and Yutaka Minobe. It's a two disc soundtrack that only saw a limited release in the U.S. and has been out-of-print for a good number of years now. Every so often you can find a few used copies on Ebay but I've seen them as high as $250.
I've uploaded both discs with each track tied to it's respected composer and I made a small modification but it improves the soundtrack overall and that is track 23 of disc 2 titled "Ramirez's Theme" was originally trimmed down to 1:53 and it would fade out just as the piano is picking back up, so I replaced it with the full version which is about 3:00 long. Each disc is over 70 minutes long so they probably trimmed the song to save space but I was told that there were actually a few songs that were omitted from the soundtrack, those songs are: Clara's Theme, DeLoco's theme, The Great Crystal Chamber, Piastol's Theme, Moonfish or Maria's/Doc's Theme and the Dark Rift Theme. Once I'm able to, I'll upload them to the Eternal Arcadia Sound Track page as additional songs or if you're reading this and happen to have a decent quality recording of the song and would like to share, send me an e-mail and I'll get them uploaded.
Those 5 missing tracks are now uploaded onto the site. Enjoy!