Lots and lots of posts here and too many for me to quote and respond to individually.
I'll just share my perspective as I was one who stored food long before the economy took a turn downward.
I grew up in an agrarian community where folks always put in a garden and everyone canned and froze the garden excess. It was just the way things were done. We didn't do it because we were afraid the economy would collapse. I suspect at least part of it was due to low incomes and memories of leaner times.
For those who worry that they don't know how to do something, the best investment, IMHO, is skills. If you can learn from books, go visit your local library. Both canning and sewing manuals have great pictures and step-by-step instructions. Your local community extension office will be a great resource as well. Some even have classes for adults.
If you need to be taught in a more hands-on method, see if you can sit in with some 4-H kids while they learn. Some sewing shops offer classes (for a fee).
As for equipment, previous posters have mentioned it but it bears repeating - water bath canning can be done with ANY large pot that will boil water and hold pint or quart mason jars. I got mose of my canning jars either free through Freecycle or low cost at garage sales. I check them carefully for cracks before each use. The only new items you *must* have are new lids. They run under $2.00/box in most areas. New rings are nice, but good condition used rings are fine, too.
Pressure canners are pricey, but for our family it's a worthwhile investment. I like the convenience of having home canned meats and soups in my pantry. I can buy local organically raised meats and put them up for later use.
Sewing equipment can also be found at a low cost. I admit it, I'm a hoarder when it comes to my notions and fabrics.
But it's not because I fear that clothing will disappear from our economy. I love sewing and can't pass by a 10 cent zipper or fabric at 50 cents a yard.
I've purchased many a sewing machine at $5 or $10 at garage sales only to pass them on to someone else who needs one! I think the best sewing machine for a newbie to use is a well maintained 1950's or '60's Singer Featherweight. They're workhorses that will take care of your basic sewing needs are typically widely available. Ask around in your community to find out if families have one they're not using anymore. In my area just about every household with a woman over the age of 60 has one.
Sewing patterns are available here for anywhere from a nickel up to a quarter. You can also google online to find free tutorials and printable patterns. In a lurch you can always take apart a garment and use that as a pattern adding in a seam allowance.
Now to address those folks who think food stores are a waste because they're not used and if you need to bug out it's money wasted:
I eat what I store and store what I eat. Yes, if my family had to evacuate we'd only be taking along our 72 hour kits and whatever excess we could transport. But that isn't reason not to store. I'm not storing food only in case of natural disasters. We store for so many reasons and that is just one of them. I don't think being prepared is ever a wasted effort.