www.askdrsears.com has a great section on cosleeping safely and how to know if it's the best choice for your family. I suggest starting there. I believe Dr James McKenna also has a website and he is very pro-cosleeping so he'd probably have some info as well.
Re: Co-Sleeping Question...
I read Dr. Sears' website.
https://www.askdrsears.com/html/10/T102200.asp