Unless you're a developer, you'll want to find one. Preferably in America if you want to get anywhere.
Your best starting point would be if you have any friends/family who are sotware developers, they can at very least offer some detailed guidance and feedback. As others have said, the biggest risk you face at the outset is you don't want a developer to steal your idea. Having said that -- and please don't take offense to this -- 99% of the time when someone thinks they have a great idea for a hugely succesful app, it's either not really a good/feasible idea or it's already been done.
You're either going to have to pay a developer, or find one to work with you as an equity partner. The latter is difficult because developers are getting pitched on "sweat equity" projects frequently and are rightly very skeptical by default. But if you really do have a good idea you'll be able to find a sweat equity partner.
The rest is tricky because most developers suck, lacking the combination of project management, technical, logistical, business, costing, estimation and other skills necessary to pull off projects successfully. Don't hire anyone with less than 6-7 years of serious industry experience. That's the best advice, really.
Oh and if you have a friend who is very experienced in the development industry and they don't want to do the project, it woudl be smart to ask them if they'll at least help you manage it. One of the biggest failure points in outsourced development projects is that the hired developer is being managed either by a non-developer or an inexperienced developer, so they have no concept of whether the hired developer sucks or not, and no concept of whether the project is going smoothly or headed for a cliff.