OK Divine, not too much around about dear Pierre! As you say, most of the references are modern day, but I did find the following:-
There is a picture of your boy at:-
http://www.motorracingretro.i12.com/gp34/34mon12.htm
If you follow that site through, you may find some more info about him.
If you visit Stefan's Le Mans Register you will also find the results of the 1939 race:-
http://user.tninet.se/~aiq291w/1939.htm
Interestingly, there are references to a Pierre Veyron taking part at Le Mans in both 1949 and 1953. See:-
http://www.silhouet.com/motorsport/a.../53lemans.html
and
http://user.tninet.se/~aiq291w/1953.htm
I haven't got time to check out any more for the moment. If you want to find out when Pierre raced at Le Mans (and we seem to know he raced there 4 times
before 1939), Stefan's results pages will probably tell you, as will the archives at the
www.silhouet.com site, I dare say.
Happy hunting!