I'm working on estate taxes, and the estate sold some land. Where do I put the 1099s in turbotax business?

Land? If that is the case, then start as shown in the screenshot below.

You will enter the transaction in a similar fashion as if the estate sold stocks or bonds.

There is no place to enter the 1099-S form in the program ... instead the info from that form is used to report the sale in the proper section of the program.