Susan,

I went to the LA Courthouse Archives today and looked up the divorce record for Wilfred Warnock Jr and Christine Amy Warnock. Divorce records seldom give the maiden name but by Section 426a of the Code of Civil Procedures the following 6 items must be listed in a divorce proceeding.
(1) Place of marriage: Las Vegas, Nevada
(2) Date of marriage: June 8, 1940
(3) Date of separation: February 20, 1954
(4) Children of said marriage: None
(5) Names of children (if any):
(6) Ages of children (if any):

The divorce was filed on 30 Apr 1954, the interlocutory decree was filed on 16 Jun 1954 and the final decree was filed on 14 Jul 1955. I believe that there was a mandatory 1-year waiting (cooling off) period required in the 1950s between the interlocutory and final decrees.

OK, so now you can send to Las Vegas (Clark County) for a copy of the affidavit for marriage application and this will show her legal surname at the time of the marriage. If she had never before been married then this would be her maiden name. The address of where to write is:

Attn: Marriage Bureau
County Clerk's Office
P. O. Box 551603
Las Vegas, NV 89155-1603

Be sure to ask for a copy of the "Affidavit of Application for a Marriage License" because if you just ask for a copy of the license you will get a different document which just states that they were married and no other information. The fee for this service is $8 and a personal check is OK.

Good luck,
Larry