There isn't one single source of information that will give you everything you need to know about any single subject, to include emergency preparedness. This is the beauty of the Internet and your ability to search for pertinent information on almost any topic.
Even better is when someone has done that for you. See 30 Blogs With Great Info on Emergency Preparedness which was shared with us by Sandra McAubre who runs the blog www.hireananny.org
Check it out and see if you agree with all the information. I always say, take what you can use and don't get hung up on some aspect of the information that you don't agree with.