Cracked Contingency plans. The last one is the best I believe.
And why we don't need to worry
Cracked (again) I remember reading somewhere that some university students did an experiment about zombies using a viral outbreak as their basis, and in three days a city would be overrun. Also in three days the virus would burn out.
If you replace zombie with urban upset, then the plans could work, however a lot of them seem to rely on siege mentality defense which, IMO, is suicide (especially in a zombie apocalypse). I prefer a mobile approach, living off of found supplies and using maps to locate ammunition and other supplies. Most likely the cell networks would run for a few weeks, so google maps on a smartphone would be invaluable, provided you remembered your charger.