Mining is generating BTC with really powerful computers by having them solve a cryptographic math problem. They are only able to do that one thing, but they're REALLY good at it.
To start, all you need is internet, power, and a miner. If you're investing 10k, I'd recommend buying 6 of
these. To get mining, you just need to setup your miners and point them at a pool of your choice. There's plenty of them around here, I recommend BTCguild or Eligus. Getting the hardware up is as simple as putting in your network and pool information. If you go with the ones I recommended, there's a setup guide
hereFor a better explanation of how mining actually works,
this video sums it up pretty good