ready.gov is a good start, except they are hoplophobic. Still, it focuses on 3 days at least. That's a start.
Neardeathexperiments.com is a pretty decent site. Despite its name, its founder and head admin (NineseveN) is extremely level headed in a multifaceted approach to disaster preparedness. I consider it a religion-free version of Frugal Squirrels.
Frugal Squirrels is then another good site. A bit preachy, but good.
Best general advice I've been given and that I parrot back to folks that ask me, is think of preparations ("preps") as a function of time. What do you need to survive for 3 days? A week? 3 weeks? 3 months? a year? Indefinitely?
10,000 bullets don't do much good for a guy that only has 2 gallons of water, six cans of chili and a bottle of mustard in the cupboard. Gotta layer those preps and intersperse the "buying" of things with the acquisition of skills that help you if you're self sufficient.
My next "prep" skill is some sort of EMT or Wilderness first responder training.