Buy It

And so if you don't currently have a compost pile, and you don't know a horse farmer or anybody else who raises livestock, then you should consider buying some compost.  You can purchase it in bulk from a place like Georgia Groundcover - where you can either pick it up in your own truck or have it delivered.  You will get more for your money going this route than purchasing bagged compost from a garden center, but you might be getting way more compost than you really need and spending more total money that you want.  A possibility here for compromise is maybe to go in on a truckload with a neighbor or friend.

For those looking to buy a smaller amount of bagged compost, you're going to find a few basic types out there.  The following is a description with photos taken while on a recent trip at Lowe's. 

Soil Conditioner: This isn't so much a compost as coarsely-ground pine bark material.  It doesn't add a lot of nutrients to the soil but works wonders to break up the soil texture in order to improve drainage and make it easier for roots to grow.  When I worked at a plant nursery in high school, we would always recommend that when you are digging up a planting hole or a bed that you count the existing soil as 1/3 of your planting medium, add an equivalent amount of soil conditioner as the second 1/3, and use a rich compost for the remaining third. A simple way to think of it is to buy a bag of soil conditioner and either a similarly-sized bag of compost or 2 smaller bags of compost.  Since you should be digging up a minimum of 6"-8" of soil, this amount of soil conditioner and compost would ideally fix up a bed the size of the soil conditioner bag.  This is certainly an ideal situation - if you can't afford that much soil or compost - again, do what you can and add more in the fall or next spring.

Composted Manure:  This is any sort of manure that has already been composted and is ready for direct application to your garden.  My experience with purchasing this type of compost  is that the worse it smells, the better it works in your garden.  I've used some cheap stuff in the past that had no smell and really felt like black sand.  Highly questionable stuff in my opinion - did not seem to do the trick at all. Black Kow and Black Hen are suitable choices, but my favorite has always been mushroom compost.  Mushroom compost is a mixture of manures that was composted and then used to grow mushrooms in.  Apparently they can only grow one crop of mushrooms in the compost and then they have to clear it out and start with a fresh batch - so they sell it off to folks like us.  There are plenty of brands of mushroom compost out there, and here again - the worse it smells the better the compost.  And also the more expensive.  And I guarantee that after working with this stuff, the next time you buy mushrooms - you'll be washing them better than you used to.

Growing Mix:  This would include a wide variety of products, usually having some sort of fertilizer as one of the ingredients.  Like this one shown in the photo, they may be called a "Garden Mix" or "Gardening Soil" or "Potting Soil" or the like.  Many of these are peat moss based, and I'm not a huge fan of using peat moss as a soil amendment here in Georgia. When really dry, red clay tends to repel water; when really dry, peat moss tends to repel water.  When really wet, red clay tends to hold its water longer than what is best for plant roots; when really wet, peat moss tends to do the same thing.  In my opinion, the best use of this type of mixture is either in a raised bed or in container gardening where you're not actually mixing it in with red clay.  Also, if your goal is to garden organically, read labels carefully as often these mixes may include synthetic fertilizers, chemical pesticides or fungicides, and even synthetic compounds that are intended to improve water retention.  

As you're making your decisions about what you are going to add to improve your soil, head out and dig up a little.  The harder and redder your soil might be, the more you should consider investing in some good compost.  Some of you may have a lot of organic matter existing in your soil, and if so, get out there and do a happy dance!  The current condition of your soil will likely determine the size of your first garden effort.  Feel free to start as small as the size of your bag of soil conditioner!