Most foodplot info can be found under "forages" at your state university agricultural department. Alabama is ....

http://www.aces.edu/department/cotton/forage.html

For a fall/winter foodplot you can't go wrong with clovers(legumes) and brassicas(rape/turnips). Roundup the area several times to minimize weed competition, lime per a soil test, and use a low nitrogen fertilizer, such as a 8-20-28, that is high in phosphorus and potassium. Rape needs more nitrogen than the clovers.

Once learn what grows well in your area and what kind of soil it needs you can select/create your own seed mix. You can get seed mail order, or from local farm seed mills and save money over the expensive name brand deer seed mixes.