Cool discussion!
Vfem, wouldn't this make a fabulous topic for your gardening column?

In this economy, with "Victory Gardens" being very popular again...
Well, we may be a slightly biased lot, but I think all the replies here have been pretty objective!
From my own experience, I would say YES, it is cheaper to grow my own veggies and fruit. But there are many factors involved in your methods that affect that.
Can you put a price on the flavor of a homegrown strawberry or a vine-ripe heirloom tomato? I think it would be a very commanding price if you could!
You'll need to consider your personal objectives before you begin, and I agree, you should definitely start small. See if you like it...if it's for you. If you spent $50 on plants and seeds and killed them all, yes, you'd be at a loss. It takes a certain degree of love and devotion to a garden to make it prosper.
I also take into account the value of gardening to me as an enjoyable hobby, a practical form of exercise, and weeding--IMO--is the best stress-relief therapy in the world. I love to pull them by hand! Call me crazy...ha.

I can't count my time in the garden as a cost because for me it is a labor of love.
There are a lot of ways you can control your costs in gardening too. A little creativity and ingenuity can save you a lot of money.
Here's a few examples:
Borrow or share a tiller (although I would say, in probably 5-10 years of major gardening, this purchase will pay for itself).
Obtain free 5 gallon buckets from your deli rather than purchase decorative plastic planters.
Save seed from year to year (as applicable to certain types of plants).
Start your own plants from seed (for the cost of two hard, tasteless, pathetic, store-bought tomatoes I can buy a pack of seed and grow 50 tomato plants that will produce bushels of flavorful tomatoes that I can can and give away to friends and eat on fresh until they come out my ears.)
Don't buy boxes of fertilizer or bagged compost. Anyone can make their own compost and depending on where you live you can often obtain mountains of farm animal manure free for the hauling. Even city-dwellers can find organic matter for composting free for the asking (coffee grounds and veggie scraps from restaurants, etc.)
If you go with raised bed gardening, there is no need to go to Lowe's and spend big bucks on composite lumber kits. (Search the forums here for lots of info on raised bed gardening.)
There are many ways to cut corners and save money if you want to. Don't believe everything the HGTV and DIY shows tell you!
I think gardening is especially cost effective if you do it to supplement your food costs year-round. A water-bath canner is a very small expense for what you can do with it (or borrow one!) Tomatoes did well for you? Can whole, as sauce, salsa, ketchup, etc. Jars are reusable and can be purchased cheaply at yardsales. If you have a basement or garage, many veggies can be stored over winter (like apples, potatoes, carrots, beets, winter squash, etc.) I love "shopping" in my basement! If only for what I save by preventing frequent trips to the store and avoiding impulse buying--it makes it worth it.
Quality and healthfulness are a big issue for me as well. I like knowing my food hasn't been drenched in pesticides and that it's clean and fresh, and picked at the peak of ripeness.
Consider what you would pay for a half-pint of raspberries or blackberries at the store... You can pay about $8 for 3 plants and they are very low maintenence. You can grow enough berries to eat fresh, make pies, and can jam. Certainly cheaper than buying them. I spent $18 on 50 strawberry plants last year and had strawberries coming out my ears.
Ultimately it should be something you enjoy doing. If you find it tedious or don't have the time to keep up with it, you won't get so much out of it as many of us here do. I agree with jamespm_98, start small and see if it's for you. I would not go out and buy tons of equipment and seeds all at once. A small container garden or a 3x12 plot is enough to start some tomatoes, peppers and squash in and if you do well and enjoy it, expand gradually from there.
Hope you have fun and eat well next summer! :happy_flower :tools :rainbow-sun