There are a few that can learn sing the most noteworthy is jigglypuff.
at mt. pyre
Evolve Snorunt. Snorunt can be found in Shoal Cave Ice Room
you can't get the black flute in leaf green but you can in Pokemon ruby, sapphire and emerald then trade it to leaf green.
yes in Pokemon sapphire you can catch a Pokemon that knows dig mainly trapinch and sandshrew
ABXY
Sadly, no. The creators of the game forgot to add in the Pokedex, so trading is impossible without GameShark. :(
use action replay
the ones that i no are relicanth, slakoth( and his evolutions )
linoone at level 35 i think
dfg tyhgtg
You can download it at 4 SHARED.
yes there is. just fly there if you can