I got this census info at my local LDS family history center using their Ancestry.com subscription. Tomorrow, I will be at the public library and I will be on their genealogy floor. I will look for your marriages.
If you get stuck, you can always order the original application for social security by Dorothy Austin. It would provide her father and mother's names. This would cost you $27 to Social Security, and you can print a form letter off Rootsweb.com's website.