This year's plan is for a variety of herbs (parsley, basil, mint, chives, rosemary, sage and thyme), the old staples (tomatoes and cucumbers) plus some new additions to the mix (lettuces, zucchini, broccoli and spinach).
Now, while I have a large yard (15x15 lawn in front, 90 foot driveway, 15x30 patio/backyard), my planting space is actually quite limited. I currently plant in a half wine barrel (the greatest thing ever) and 2 flowerbeds that are about 3 feet wide and 12 feet long, which, when things get to growing, can be a little tight.
The key to a successful garden is planning. Planning planning planning. How long does it take for crops to grow? How big do they get? Can one crop be harvested and another planted in it's place?
For those of you starting off, do your research: iVillage has a good beginner's guide to planning a a garden. Definitely heed the advice on creating a healthy soil environment and on using mulch to keep weeds down (unless you're weird and like weeding all day in the hot summer sun). One note on the mulch -- don't use cocoa bean hulls. Been there, tried that -- the dog kept trying to eat the mulch. Also, timing the planting to occur at different times (or once faster-growing crops are harvested) is also a good idea, if you want to sustain the availability of home-grown goodies all season long.
If you're like me and have limited space, consider a container garden -- even if it's just some herbs and a tomato plant. GardenGuides.com has a good how-to if you want to take the plunge. Basil and parsley are easy starters, and certain varieties of tomatoes are quite hearty. I typically plant my herbs in a half wine-barrel, and make sure to replace the soil each season to maintain it's health. Despite what many say about rot, I haven't had this problem with my barrels. It helps, though, if you fill the barrel halfway with packing peanuts and a plastic shopping bag before adding the soil (you don't need all that weight or depth for shallow-rooted plants) and then keep the barrel off the ground using some small bricks.
Get ambitious and plant a garden this spring. Your wallet and taste buds will thank you!