I got an email from the daughter of someone that sailed for Isthmian Lines. She was on Ancestry.com looking for the 1940 census information. She searched on her father's name a found a crew list for the SS Steelmaker with his name on it. I tried searching on my father's name and found some hits.
Until April 10, 2012, at midnight, Ancestry.com is offering free access to some of their databases.
Ancestry.com (click here)