Your indoor or part-indoor vegetable garden layout can have a big impact on both the success of the veggies and how much you use your home grown produce.
One of the most important things in my opinion is to have your vegetable garden as close as possible to your kitchen, or entirely in your kitchen if it's a container vegetable garden. This way, you will see the veggies each day and be able to keep a close eye on them. It's also convenient to harvest them while you're whipping up a meal.
Your veggies will most likely be in a number of pots. The container placement will depend on the available light and the space. Lettuces don't need as much light as some other veggies for instance. And your tomato bush may be a little too big to fit on your windowsill.
Do you have a balcony? If so, it's a wonderful space that with some creativity can be home to some potted herbs or veggies. Have a look at the balcony gardening page for more ideas on using your balcony.
If you're fortunate enough to have some outdoor space, you can be far more creative with the layout of your garden.
It's traditional to plant veggies in rows, but this layout may not be for you, particularly if your space is limited! By using tiered benches, you can put plants in containers closer together and make them easier to reach.
There's no need either to have a dedicated "veggie patch". Why not mix in some attractive flowers so the garden serves two purposes -- looking beautiful and providing fresh veggies!
Be creative with vertical space. Use hanging planters or shelving on walls to accommodate extra plants in limited space.
If you don't have a yard or balcony, you'll be restricted to your indoor space and you only have so many windows to provide light. You can always look at creating a grow room or grow closet with artificial lighting, so you can make use of "dark space" for growing. Another thing to investigate is an Aerogarden type appliance.
Companion planting is when you make use of one plant to help another one. For example, planting beans near lettuce or spinach will help the lettuce or spinach grow better.
Plants can help other plants in several ways:
There's a great list of companion plants at Wikipedia. I suggest you have a look at it when planting your veggies, whether indoors or out.