I don't want to sound negative, but I see a lot of obits and biographies that make reference to service in WW1, with an Aero squadron number that is not in any of the reference books. Here are three possible explanations:
1) Typographical error - they could have meant the 370th Aero squadron, but somebody typed a 5 at the end by mistake.
2) Some of these people may have served in active units prior, and then transferred into these little-known units after the war.
3) They may have enlisted during the war, and by the time they got assigned to an aero squadron, it was past the time when anybody was keeping detailed historical records.
Basically, any aero squadrons created after about the end of 1918 have little or no recorded history in the standard reference books, and may not have much information even in the Air Force archives. I think that without combat reports, the history of these aero squadrons was reduced to mundane paperwork such as requisition and supply forms, which may not have been kept as historical records. There's probably not enough material on these squadrons to make a book, but there's a decent review of the period on the Air Force History web site:
http://www.wpafb.af.mil/museum/history/pos...wwi/postwwi.htm
Unfortunately, this site doesn't list what squadrons were active during this time. If you go back to the main Air Force History page, however, there's a link to e-mail a historian at the USAF. You could give that a try and see if they can find anything out, then let us know what happens.
Tim