"So, you and your friends have convinced me to become a teeny-tiny farmer, affording a little increment of potential security to my family, friends and neighbors. But I've never done anything like this. Also, I have heard how expensive a hobby it is and have almost no money to put into it. Where would I begin?"
You can do this on very little (as do actually most of the farmers in the real world). But it eventually requires of you more knowledge than you would gain from getting a master's degree in most subjects. It's that, I think, that makes one hesitate.
Fortunately there are many baby steps.
Let's assume that you are a suburban homeowner with a typical lot, about eighty feet wide and a hundred feet deep, on level clay in a temperate latitude, with several trees and shrubs about the three-bedroom bungalow and along the driveway and carport. You have a rake, a hose, a lawnmower with a grasscatcher, and very little else with which to begin. And you're very nearly "underwater" with a massive mortgage, and so will not being moving "back to the land" any time soon.
First, pay attention to where the sun is. Do shadows cross all of the lot all day, or part of it part of the day, and at what time of the year do they do this? Some deciduous trees on the south side of a house can be a good thing as they provide shade in summer and admit light in winter. Evergreens on the north side can be a useful windbreak, cutting winter heating bills. So don't think of getting rid of everything all at once in order to get enough sun for vegetables.
They will need some, though. At least eight hours on the planting spot, most of the year. See if you can find a site on the property where that's happening, even if it's only part of the carport.
People spend a lot of money on tilling and/or buying materials to make raised beds, or injure themselves attempting double-digging with D-handled spades or forks. There are times when these are appropriate tools or practices, but let's try a more pleasant approach for now.
If your sunny spot (existing or judiciously created by shade tree removal) has a foundation of wood (deck) or concrete (patio or part of your driveway), think containers. Any potted plant is an instance of container gardening, and at the other extreme are the glassed--over hydroponic farms of Iceland. No need to lay out cash for big containers or materials to make planter boxes. You can begin by going to the nearest Garden Center and buying some small healthy-looking vegetable starts and some fifty pound sacks of "planting soil." Lay out the bags where you want them, puncture them enough over the surface to let water drain, then flip them over, punctured side down, and remove enough of the now-uppermost surface of the bags to plant your starts in.
A great way to water your starts without overdoing it is to puddle lightly around their roots with water from a well-cleansed dishwashing detergent dispenser. It's as gentle as an expensive watering can (the cheap ones can dump too much on small starts) and costs nothing. And you can water your garden with a garden hose, yes, but the range of possibilities -- from punctured milk jugs of water to soaker hoses -- is large.
If you have some grassy area in which to begin, prepare that area a year in advance, thus: remove all packing tape and bagged invoices from a heap of collected kraft-paper (cardboard) boxes, open them out, lay them flat over the garden-to-be, and cover them with shredded leaves and grass clippings (or get straw -- not hay, too many seeds in it -- if cheap). No need to buy a shredder, your lawnmower with bagger is a cheap and powerful (if noisy and polluting) piece of farm machinery. In a year a spot so treated will almost certainly be a perfectly ready-to-use fertile "raised" bed. Between now and then, if you must garden there, try the bags of planting soil on top of the permanent mulch.
You will still need planting soil in such a garden, as anything you direct-seed that does not like cold soil will not wish to germinate in the cold soil beneath the permanent mulch, exposed in spring. Pull aside the mulch from your planting spot, add a handful of planter mix, lay out your seeds, and cover them with more planter mix, according to the depths and at the times shown on your seed packets. Later, when you have accumulated enough compost in your compost heap (which you began right away), you can sift this and that will will be your planter's mix (and much better than than provided by the stores).
Start small, my dears. Start very small. It's so easy to become discouraged after taking on too much.
In the first winter, get your fruit trees (as recommended for your area) and put them around the perimeter of the property. Get dwarf varieties if you can, or semi-dwarf; if you can't, just learn to prune aggressively so that your big standards never achieve big-standard size.
Now, if your community's rules permit, set up your poultry house and run. Chickens or ducks supply eggs (and if you are up to it, meat) at low cost, especially if free to eat grass and chase bugs. If you can possibly do so, combine your orchard with your hen-run and make them surround the perimeter of the garden. The birds will eat bugs that eat or infest fruit, and clean up dropped fruit without your having to gather it for them, and they will interpose themselves between a great many insect and mollusk (snails and slugs) pests and your permanent-mulched veggies. There's also a certain entertainment bonus as well. Careful! Too few birds, and you will see symptoms of loneliness and derangement out there; too many and you will see mostly a dismal expanse of mud.
Later, when you have acquired all the skills of a tiny-tiny farmer, you can branch out by sharecropping with neighbors who will trade access to their backyards for a share in the veggies, and when you lose your job in the big-dying-city (to which you can no longer afford to drive anyway), your splendid and life-affirming new career will be there for you, ready and waiting.
For access to enough knowledge to actually pull off the things recommended above, there is an almost endless stream of websites, pamphlets, magazines, books, videos, television programs, Master Gardeners, and kibitzing neighbors available. Just dip your cup in the stream and drink deep.
For example, go to the nearest used-book store and ask for the gardening section. There will be many classics at very low prices; you may even find enough to get you started in a free box. That's where I found the very-easy-to-read Down-to-Earth Vegetable Gardening Know How, a primer written by Dick Raymond and published by Garden Way of Charlotte, Vermont in 1975 (!!). Though some of its recommendations I no longer follow, it's still, at 140 8.5x11" lavishly illustrated pages, one of my most frequently consulted authorities.
When you cut suckers off tomatoes in the summer, allow some to get as big as your little finger and to produce a bud. At this point, remove the sucker from the plant and cut all the leaves off up to the bud. Set it in a glass of water for about four hours, make a hole in the ground, set this slip in the hole, and firm the soil around it. In a few weeks, that sucker will produce wonderful fruit, just as a plant grown from seed would. -- Dick Raymond.