Gaining Attention

Gaining Attention is an expression or the way to gain attention for someone. I you want to gain attention for someone, you can use :
Attention, please
Excuse me
Look here
Listen to me, please
Waiter ?

Response :
Wow, really ?
I'm listening
Wow that's true / great

Example dialogues :
Ina : Look here ! I see a big oreng utan .
Lisa : Wow, that's true ! It's very big.