http://www.amazon.com/The-Pleasures-.../dp/0786716487
The Pleasure's All Mine: Memoirs of a Professional Submissive
It's a fun read plus, it does offer some ideas about safety, etc. It is a memoir, though, and not a how to book. I found it to be a completely great book to read.
I don't know how you can be completely safe doing submissive work. I touched my toes, VERY lightly, into trying it and was really disappointed.
Some men aren't dominants. They're bullies. And that is what I found more so than the other. Again, my experience is very light. I've met lifestyle dominants who are the real deal.
But in the hobby? I would need to REALLY establish a lot of trust before letting someone tie me up, etc. I just wouldn't feel safe doing it, even if someone was in the other room. If there was someone watching from a security a camera (which I would find unnerving), or IN the room, I might feel differently.
The book is interesting and actually discusses these different options that she experienced.
Good luck,
Elisabeth