Penny, Olympic is among my favorites of the ships I've studied so far. I highly recommend the book "Titanic Survivor," the memoirs of the stewardess Edward K mentioned. Although it was written by Violet Jessop, it is often displayed with John Maxtone-Graham's works as he wrote the introduction and provided insight.
There is also a wonderful volume called "The Olympic Class Ships," by Mark Chirnside. It's very detailed and took me a long time to get through, but it was well worth it. I was impressed when I learned that Mr. Chirnside wrote this as a University student.