The Ancient Chupicuaro Figure is the 7th treasure in Uncharted 3: Drake's Deception.
The Ancient Chupicuaro Figure can be found in Chapter 2 - Greatness from Small Beginnings.
Right after the previous treasure, just before following Sully through the archway into the market, there will be a side street to the left. Turn down that street and there will be a small staircase on the left side. The treasure is at the top of the stairs.