This window lock is broken and I don't know what tool to use to replace the lock. It's just round hole, not a screw. I can't even identify the window manufacturer. Any help?
I am going to guess this picture is taken looking down onto the top of the lower sash of a double hung window? The wood I see at the bottom of the picture is the wood flooring a number of feet lower? If so you can drill out the pop rivets on both halves of the sash lock and replace both halves with a new unit that resembles yours as close a possible. They are available at a hardware store. You will need a pop rivet gun to reset the locks in the same way, but you may need to drill new mounting holes too if the new lock has a different spacing for the mounting holes.