I know that there will be an upcoming event for him, but is there a way to get Genesect in your pokedex before the event? (This goes for Keldeo and Meloetta too.)
No, there is no other way to get it into your Pokedex unless you cheat which is wrong. Hope this helps...
There is no way, you need to wait for the Genesect event to have it on your pokedex
(This goes for Keldeo and Meloetta too.)
There's an event running from October 7, 2012 - November 12th 2012 over WiFi.