For us beginner raised bed container gardeners, I found a neat resource for laying out a bed:

http://www.gardeners.com/

There is a feature for the 'kitchen garden' where you can lay out the dimensions of your bed then click and drag vegetables into each square foot. It gives guidance as to how many to plant in each square foot, as well as planting and care tips for each vegetable selected. The 'map' can then be saved and e-mailed to yourself for printing etc. This is a helpful resource to this 'newbie' and I hope it will help others.

Here is a link that might be useful: container map gardeners.com