If there is a topsoil sold in bulk nearby that you think looks good your best bet would be to have that delivered and dump it on top of the clay soil, without mixing them together, and plant in the new layer of topsoil.

Here is a link that might be useful: Compost overdose.pdf (application/pdf Object)

I also live in Georgia. I have had good results with adding organic material like Nature's helper to keep the clay from clumping together. There is also a similar product, I think it is called Clay Buster but it is not as widely available. The key is adding organics like ground bark.
If you get a full morning of sun, almost any periennial or shrub will do well. It may not be enough sun for the tomato.
Make the bed as big/wide as you can (6' min) and make it raised for drainage. There are way too many skinny beds out there.

When you layout the bed try for an organic shape. Curve are generally more pleasing to the eye, especially in reference to nature.

Some people take a watering hose and lay it on the ground to outline the shape and be able to "see" the bed before they commit to it.

I think better homes and gardens even has a free place on their website where you can layout your garden online.

Hope this was helpful - Miranda
Green Panther