I've been making games professionally for close to 19 years. Much of the advice in previous posts is very important, so I'll summarize all the bad points first.
1. Your game concept is worthless to anyone but you. I've personally got 30 ideas for games that will most likely never see the light of day; some of which I honestly believe are better than the very best games out there right now. Without turning that idea into a playable demonstration, no-one will give you money for it.
2. You might think your idea is brilliant (and you could be right) but chances are once you turn it into an actual playable version, you'll more likely than not find flaws and issues with the design. I've never worked on a single game that plopped fully formed from design to execution, it just doesn't happen. Expect 90% of the effort of designing your game to happen after the first implementation is complete.
3. Tens, if not hundreds, of thousands of other people want to do exactly what you're suggesting (sell their idea for money). The people with the money to give you are publishers, and the vast majority of those explicitly will not even talk about your game design, just in case it comes close to a product in development. The last thing they want is to open themselves up to being sued because your idea was remotely similar to a game they intend to ship next year.
now the good stuff:
You can make games yourself, right now. Trust me - making (and playing) your own games is infinitely more satisfying than just talking about it or writing down half-baked ideas on a piece of paper. Do what the Narbacular Drop guys did, *make it*. If you don't know how - learn. Everything you need to learn is out there right now.
There's some really good frameworks for making games out there. look for Unreal Development Kit, Blender you already mentioned, and my personal suggestion for your best starting place would be Xbox 360 development using XNA. The benefits of making your game on a platform where it's easy for everyone else to look at the end results in the cold light of day are huge - plus for a small investment you get to play your game on a proper console gaming environment (big telly, etc). There's also mobile platforms - basically, if you care enough to try and are willing to invest your time and maybe a couple of hundred dollars, you can get started on making a product that will be good enough to get attention from people with serious money.