None....It's impossible, sorry.
However, in HG/SS, you can get an ExtremeSpeed Dratini. Here's how :
> #147 Dratini
After you have defeated Clair in the Blackthorn Gym, she will send you on a quest into the Dragon.s Den. Deep inside the den you will discover a building with the elders. These Elders will ask you questions about how you raise your Pokémon. After the questions are answered, he will give you a Dratini. If you answer his questions with the compassionate responses, the Dratini will know the special move; ExtremeSpeed. If you don't answer with those responses, it will just know its basic moves.
So get this ExtremeSpeed Dratini, and trade it, or migrate and then evolve.... That's the only legit way.
Hope This Helps :)