Today we had some heavy rains and when I went in my GT there was a small puddle of water directly under the foot pedals (accel, brake, clutch) and in the drivers seat!

How did this water get there? Where should I look? I looked along the sides but everywhere is dry. This is a puzzle indeed. Little help please?

 

if it's not a convertible or t-top car , look on the firewall for it running down there due to a leaky windshield seal

 

This is from inside the engine bay no doubt. If the windshield seal is leaky, is this an easy (inexpensive) fix?