#1 Get a drum you can store clean water in and add a small amount of bleach to it every few months to keep it from getting nasty. Get one of those pitchers with a carbon filter to pour it into when you are ready to use it.
http://www.storablefoods.com/water_storage.html
#2 Bulk bags of rice are cheap and it keeps for a long time.
#3 Also have other grains on hand along with yeast and baking powder.
#4 Store sugar, baking soda and salt in a water tight containers.
#5 Have some type of cooking device and plenty of fuel such as propane, white gas, or kerosene.
#6 Store pepper, spices, tea, coffee, koolaid and other substances that make your food more palatable in water tight containers.
#7 Keep canned meats, fish, soup, vegetables and fruits.
#9 Dehydrated foods are good, but tend to be expensive.
#11 All foods must be protected from rodents, insects and other pests.
#12 Make sure that you have some first aid supplies such as hydrogen peroxide, antibiotic ointments, clean dressings, and pain relievers on hand.
#13 Make sure you have some means to protect yourself and your family.
Most of these items are relatively inexpensive. You don't need to spend a lot of money on expensive “survival” stuff. You should be using these supplies on a regular basis and replenishing to keep them relatively fresh.
Gardening and other long term survival skills are good to keep up on, but seasonal. If you live in a place where you can keep some animals that is great, but remember that they could be vulnerable to other desperate people.
And don’t forget cooking oil, peanut butter, dried milk, dried eggs, cocoa powder and bulk chocolate. Potato flakes are your cheapest dehydrated food and can be added to any broth to make it much more filling.
Believe it or not, two of the most valuable objects for trading purposes to stock up on are half pints of alcohol (vodka, gin, bourbon), and anti-diarrhea medication according to the guy in Serbia during the Clinton Bombing years. Also 22 short and long rifle ammo is a valuable asset both to have and trade.