If you're new to game development and came to GameDev.net with a game idea, hoping to...
Sell the idea to game developers that'll make the game and pay you/split profits with you, or
Lead a group of developers to make the game under your management
...then I've got some knowledge to impart to you. This is actually the very reason I first joined GameDev (because I had a game idea), and I was taught the same lessons I'm about to teach you.
Clearing your Delusions
This first part is going to be taken up mostly by me shattering your dreams. It's tough, but in order to look at your situation realistically and consider how to make your game, you have to first understand what's not going to happen and how things just aren't going to be.
I have an awesome idea for a game! How do I sell my idea so I can get rich off of it?
This isn't how it works. You most likely won't be able to pitch a game idea to someone or some company and have them make it for you. You pretty much definitely won't be able to actually sell the idea for a huge check or a percentage of the profits that the game makes.
This is because games are mixtures of quite a few different fields - to name some of them: programming, art, music, sound effects, and in some cases, writing for the world, story, characters, dialog, etc.
These are all rather extensive fields that require skill and knowledge to implement well. Games are tough to make. They're combinations of both artistic and technical fields, each one requiring time and dedication to get skilled with.
The idea for a game, the raw concepts for it, are a tiny fraction of what's involved with making a game. Not only this, but game ideas are often changed a lot during the process of developing them; the original idea probably won't even be that fun, even if it seems like it would be when you think of it. That's why people make short demos of their game ideas and play-test those demos to see if their games are fun. They tweak and iterate on their ideas until they're polished and fun. Very rarely (if ever) does a game idea just come to someone, perfect and ripe for development, ready to make people rich and entertain on a meaningful, worldwide level.
So...in short, it's very unlikely that you'll sell a game concept/idea, because game studios have lots of these (pretty much anyone who's into game development has their own ideas), and they don't consider them particularly valuable. What's truly valuable is the implementation of those ideas, and how you turn them into an actual game: that's why the playtesting and tweaking part is considered so important.
If you want your game idea to be developed, then you'll have to do more than throw around concepts and ideas, especially since you're completely new to designing games - and playing lots of games doesn't qualify you, either (though it does help).
OK, in that case, can't I just find game developers and get them to make my game?
Now that you know you won't be directly selling your idea to people, you may consider trying to gather a group of game developers to make your game for you, while you tell them how everything should be.
Game Designers and Idea Guys
Before we go on, I feel it's time to clear something up: the common title for "the idea guy" is called a 'game designer' (even though that kind of sounds like they make graphics or art...it confused me at first).
At least in the GameDev.net forums, people have separated the Idea Guy and the Game Designer into two different kinds of people:
The Idea Guy is one who has vague ideas without providing very many useful, specific details. Like I said, the majority of a game is its implementation and polish, and the actual, high-level ideas, though important, are only a small part of the creation process.
The Game Designer is one who provides ideas and concepts as well as digging deeper to fill in a lot of technical details (such as how much damage and health things have, how fast the player moves, and so on). Game designers understand the importance of iteration and playtesting when creating games, and know that games are very unlikely to come straight out of their heads as pristine magnificence. For more information on specifically what a game designer does, check out this article.
Okay, now, back to the topic at hand: gathering developers to make your game for you.
This idea is mostly unrealistic unless you can pay those developers. If your game is as big as Call of Duty or similar, then this entails paying the salaries of a team of developers for at least a year. I've said it before, and I'll say it again: games aren't easy to make, especially triple-A quality games like Call of Duty, Final Fantasy, World of Warcraft, and so on. It takes a lot of money and expertise to push out a game like those.
If your game is smaller (and you should start small!), something like a simple mobile game that doesn't have an RPG-like need for content, then you'll be much better off.
If you can't pay developers, and you just expect them to make your game for you "because it's awesome", then you're going to have a rough time. Specifically, you'll probably end up only attracting people who aren't really that good at what they do, or you'll just be ignored entirely.
The reason behind this is because you, as an idea guy/game designer, aren't really in low supply or high demand. In fact, when you're on game development sites looking for developers, the chances are they all got into game development to make their own ideas, not to do it for other people...for free.
The gist of it is: you can't expect people to do hard work like making games for you unless you can pay them. If you can pay them a reasonable rate, then that greatly increases your chances of getting your game made - but you should research and make sure you know what you're doing before you start trying to hire developers.
Okay, so it's impossible to make my game without money?!
Whoa, whoa, calm down there! Things may be looking a bit negative now, but there are still ways to make your game: you can do so by harvesting the power of "doing things yourself".
That's pretty much the point I've been working towards up until now: your chances of turning your game ideas into reality...er, virtual reality...are going to get higher and higher the more you know about actually making games.
If you learn and get good at some kind of game-development-related skill, like one I mentioned above (programming, art, sound, etc.) then you'll be much more respectable in the eyes of hobbyist/indie game developers. If you're actually a good game designer (which also takes practice and research!) and team manager, and have at least one skill to contribute other than game design, then gathering a team of hobbyists and making a game is achievable, as long as you have reasonable expectations (i.e., aren't expecting a huge, triple-A game to be the result).
Summing it up
Games are hard to make, and big games like Call of Duty and Final Fantasy are created by teams of many paid developers: programmers, 2D and 3D artists, music composers, sound effect designers, etc.
Even hobbyist game developers who don't have a job probably aren't going to make your game for you if you don't pay them for it, because they have their own ideas and dreams that they'd rather work on.
Fighting the facts won't get you anywhere; the sooner you realize game ideas are a dime a dozen, the better.
Learning a Skill
Now we've learned that if you want to make a game and you can't pay for it, then you'll be a lot better off if you have something to contribute to the development of a game. Simply being a 'game designer' isn't ordinarily enough to entitle yourself as a true 'developer', because, although design is important, so much more goes into a game than just design. As well as that, you probably aren't necessarily a good game designer if you're new to game development in general - no offense.