It's around the top area.
The poke flute is a radio channel on the Kanto radio gear. After you have solved the problem of fixing the powerplant, go to Lavender Town. Go into the radio tower and talk with an old man in there. He will give you the radio gear for the Kanto region. Select the radio in your pokegear, and search for the poke flute channel towards the end of the radio signal.
at the kanto radio tower
at the radio building in lavender town of the Kanto region
You don't get an actual flute. When you find the missing part in Cerulean City for the Power plant, go to the radio tower in Kanto and the director there will give you a card that lets you play music from Kanto. The Poke flute channel will be on that card.
Guess what the poke flute doesn't exist in your radio you can tune into a pokeflute channel but only in kanto.
The poke flute can be used in between the first line of circles, just go strait up to access it.
In your radio, all you do is go to the top of your radio with the little dot and then it will say poke flute and then you can get that awsome snorlax that is blocking diglets cave. (but the poke-flute channel only works in Kanto not in Jhoto)
You must get restore the power back to the Kanto Radio Tower. To get the power back, you must find the Kanto Power Plant's missing piece.
To get the pokeflute in Heartgold and Soulsilver, you must go in the Kanto region and must be able to use the radio in the Pokegear in Kanto and when you use the radio, put it all the way on top.
you go to the radio tower in KANTO in lavender town after you settle the power plant problem them talk to the man with the brown hat,suit,and pants then he will give you the poke flute and you spelled flute wrong.
You don't actually get it. When you get the Kanto radio card you turn on the radio and move the signal to the top middle.
to use the flute in heart gold you must have a radio go near a snorelax and use the styalus to find the station that the poke flute is on you can not use it in jahoto though but in kanto you can.