the exact place to blow the flute is right next to the green rock (maybe it's a rock?) in the screen where you first met Leah. stand to the left of it, blow the Beeba Fllute, and the Wingapede should come

the first time i reached this party, the Green Dragon gave me a million stats and i had to walk all the way back because of Sprain. and i didn't have a Brace -_-'