iPhoneDevSdk.com has a forum for that.
Make sure you prepare an NDA before giving the idea away though and be prepared to pay more for the dev or get a smaller share of the profit that you expect.
Having an idea is easy, implementing it is the hard part.
Now that's the dumbest thing I've heard.Implementing it is the easy part
That's the dumbest thing I've heard. Coming up with the is hard. Implementing it is the easy part, it's transforming idea that is some what difficult. But should be rather easy. Now, the hard part on the iPhone, is that much of the memory is limited and that is a lot of work.