If you mean where you can get Fly, it's in the Team Galactic warehouse (nearby the HQ) in Veilstone City. You will not be able to access the warehouse, however, until after you have beaten the gym in the city.
Chat with our AI personalities
staravia actually does not learn fly you have to teach it an hm.
You capture a Pokemon that has wings and find HM fly teach it to the Pokemonthat you caught and then go on to the menu and click Pokemon and thenclick the Pokemon you caught and then it says fly and just click fly.
You need to teach it Fly. You can find the HM Fly at the Team Galactic warehouse, but you need to defeat the Gym Leader of the city first.
Yeah it also works on diamond get a flying Pokemon lets say staravia teach it fly and click fly and it will say where to click a place you want to go to. :-)
catch a Pokemon that can learn fly, put it in your party, and WALA! you can teach it fly!