1. The easiest way is to purchase the sheet music or songbook for the song. This will contain the complete arrangement, including the chords and choir parts.
2. You can also find a chord chart for "Are Souled Out" online, which will show you the basic chords used in the song. Then you can add choir parts by ear or by following a lead sheet.
3. Finally, you can also hire a session musician or music copyist to write out chords and choir parts for you.
Here are some specific resources that you may find helpful:
* The sheet music for "Are Souled Out" is available for purchase from varios stores.
*You can also find chord charts for "Are Souled Out" online, such as ChordU.com and Ultimate-Guitar.com
*If you would rather hire a session musician or music copyist, you can do so through websites like Fiverr.com or Craigslist.com.