You don't have to dig up an area or worry about weeds to have a garden. In fact, you can create a garden in about an hour, and never have to weed, till, or dig it again. Here's how.
Get some boards and some big cardboard boxes or newspapers, and find a flat space where you want a garden. The boards don't have to be fancy--I use scrap lumber that I find washed up on the beach after storms. If you're very particular about the way things look, then stop by the hardware store or lumberyard and pick up some 2 x 6s or 2 x 10s.
These are 2 x 6 boards. (This means they are about 5 1/2 inches wide, and 1/1/2 inches thick). This garden is going to be 4 ft by 5 ft, because that's the length of the boards I happened to have on hand from my last after-storm-scavenging session.
If you need cardboard, stop by any bike shop. They have big, flat cardboard boxes and they are always looking for people to take them away.
Cut your boards to length if you need to, and screw them together at the corners:
The rusty screw was already in the board from before--this is scavenged wood. I added two more. You can nail the boards together if you want, but they are more likely to come apart eventually.
Basically you are making a box with no bottom, like this:
Lay cardboard and/or newspaper over the entire bottom of the box. It's a good idea to have the cardboard extend beyond the edges of the box--it keeps the weeds at bay a little longer:
Watch out for cracks where the boxes had flaps, like this:
Weeds will find that crack and grow right up into your garden. Cover the crack with more cardboard or newspaper--if you use newspaper, make it at least 6 pages thick. Try not to use pages with a lot of colored pictures, as the chemicals in the ink may get taken up by your plants. If it's a flower garden you might not care about this, but if you're going to grow vegetables to eat, it's good to be careful.
Fill up your garden box with layers of compost, manure, topsoil, straw, peat moss, seaweed, sawdust, bone meal, fireplace ashes, leaves, grass clippings, or any other organic matter you have access to. Top it all off with a layer of straw:
Water it all really well. If you want to plant in it right away, make sure the top layer is something finished and ready to plant in, like topsoil or finished compost. If you don't need to plant right away, cover it with straw or beach grass to prevent weeds from growing in your garden bed.
If you don't have "finished" materials and all you have is grass clippings, leaves, etc., then just let it sit til next season and by then everything in it will have composted down into soil--you're ready to go.
When you do plant, mulch around your planting with more straw or beach grass. This will prevent weeds from growing and it will also keep the garden from drying out. The plants will stay evenly moist, you won't have to water very often, and best of all, you will have NO WEEDS.
Here's a photo of some tomato plants growing in this type of garden:
Notice, no weeds, no work, no problem! The only work you ever need to do with this kind of garden is at the end of the season, you need to bring in more materials to build up the bed. More old leaves, grass clippings, compost, seaweed, straw, etc. That's it.
If weeds ever do sneak in, they should be easy to pull out because the thick mulch prevents them from really getting a grip on the soil. If they manage to take over anyway, just smother them with another layer of cardboard and put more organic materials on top of that. Bye bye weeds!
Warning: this method is so easy, it can be addictive. You may find yourself looking at corners of your yard and thinking, Hmm, I could put a garden there...
Helpful books:
Lasagna Gardening, by Patricia Lanza
The Postage Stamp Garden Book, by Duane Newcomb--absolutely the best and most useful garden book I've ever read. In simple, easy to understand language, he explains how to "fix your dirt" in simple, easy-to-understand ways, and make things grow like crazy. This is something no other garden book had ever done for me--this is the book that really made me a gardener.