If you are interested in a firsthand account of what steerage was like, you should read Eliza Putnam Heaton's book: The Steerage: A Sham Immigrant's Voyage to New York in 1888. She was an American author who wanted to find out for herself what it was like to immigrate to America in steerage. She went to Liverpool and bought a steerage ticket back to New York so she could write about her experience. I really liked it! It is only 45 pages long, so it doesn't take long to read.
You can read it on this website: http://nrs.harvard.edu/urn-3:FHCL:884325