Here at the office, one of your fellow community gardeners, Kass, has been planning her garden. But she hasn't been planning it with graph paper and a pencil. She found this great website called Grow Veg - the Smart Way to Plan Your Garden and has been planning her garden online.
This website allows you to plug in your garden dimensions, choose your style of planting (row or squares) and even tells you the setting out date for our location. It's easy to use, versitile and when you are done, you can print it out.
You can pay for the full program, but there is a free 30 day trial (just enough time to get everything in order before planting, in my opinion!).
If you are a new gardener or experienced, give it a try.