You have the idea, and if it’s truly a good idea, then that’s worth a lot. It’s worth more than “simple coding”, too. So you have to treat it with that kind of value.
What you need to do first is write it up as clearly and simply as you can – a page or two, if you can limit yourself to that – to give a non-coder an idea of what the idea is, and then you need to write it up again with pseudo-code to describe the processes in a way that the techniques of the idea are captured on paper. Then enlist an attorney on your behalf to review what you’ve written and draft a Confidentiality / Nondisclosure Agreement.
That agreement is what you’ll take to potential coders, which you can find via google or any other search. There are a lot of out-of-work coders right now, so it’s truly a buyer’s market, and you’re the buyer here. Shop a lot and meet people face to face during your second round of interviews. Be very careful here, because you’re essentially shopping for a business partner or two. You should also be very clear at this point that this is a partnership arrangement, that you’ll retain at least 51% control, no matter how many other partner-programmers are brought into the team, and there’s no salary involved for now. This is all on spec.
When you find one or more that you feel you can work with (and can work together, if you decide to break up your plan into modules, which is an excellent idea), then have them read and sign the NDA and return to you. They shouldn’t have any problem signing that; after all, the only loss they could suffer at this point is not seeing your idea. (The NDA doesn’t prevent them from stealing your idea, of course, but it gives you a hook to mount a lawsuit with an excellent chance of winning, should they strike gold the idea that you have shared with them, with the explicit understanding that they won’t use it against you.)
When you have your small team in place, and your “partners” understand that there’s no money to be made until you have something working, then let them have free rein to put your idea into mockup reality. It may be too soon for a functioning website, because others with deeper pockets than yours could stumble on that and steal the idea and not owe you diddly. So you need to keep this strictly under wraps until you have something that works, and can be readily implemented and scaled up if it takes off. (You wouldn’t want to invent Facebook, spend all the time perfecting it, and then do a half-assed release, only to watch someone else do it better and steal your thunder.)
When you have something that works, and before you have made it public at all, now you need to find a venture capitalist and sell that person on the idea. Then you’ll have the resources to start paying your partners (and yourself) a modest salary and cover your out-of-pocket expenses, and release a fully functional, tested, backed-up implementation – and pay to promote it heavily.
Good luck.