temple of gust or you can buy it off of Beedle.
first your arxeidia
You can't, sorry
there 4 i think
You get it in the temple of wisdom.
in the courage temple on molida island
the bow is on molida island in the courage temple
the island of ruin
they are the warping phantoms if they another phantom or a phantom eye sees you they will warp by you
you must lower the water
find the sun key
take it to the sun door on molida island
You can find it on ebay for cheap around $17