The Later Day Saints has lots of good information on food storage and even has a food calculator you can use. It will give you a good baseline to work off of.
You can also check out thesurvivalpodcast.com and todayssurvivalshow.com for good practical information.
Sound advice for storing foods is to buy extra's of what you already eat, store some spices, toilet paper and water.
As for some long term storage, keep several days(or weeks, etc) of freeze dried, dehydrated foods and/or some MRE's. You can also dehydrate some of your own foods for storage but it won't last as long as packaged goods.