Like every other Southern state, there were auction block sales in the larger towns but unless the auctioneer was selling off a dead planter's "inventory" there would be no names associated with the individuals sold. The best sources are either in planters' wills and probates, or in bills of sale that were recorded with the courts (usually in either the deed books or in court minutes where the planter just swore or spoke before the court, saying something like "I notify this court that I am selling Jim to John Doe for $800 on this day, April 6, 1843")
Published wills (or will books you can go through) for the county or counties in question are really the best place to start.
Be sure to look at the 1866 marriage records for your folks in the county where they lived. These are the first legal documents most slaves ever signed or were involved in and can give you clues. Marriage certificates were the first encounter a slave would have that would require a surname and they may have made them up on the spot. If you can look at the actual marriage book, pay attention to who was standing in line together.
If your people ended up with land or even as tenant farmers, pay attention to who was involved in the transaction. Also look for Freedman Bank Records for your folks and other folks in the area to get an understanding of who owned slaves in the area and whether or not slaves took their surnames. Some did, most didn't. Keep in mind that siblings did not always select the same surname and it sometimes takes some painstaking studying of census records to see who is related to whom. It always pays to look at civil and criminal records (whether the charge was real or trumped up) to see the details/names and who might have been kind enough to post bail/bond.
Best of luck.