If you're on somewhat of a budget, either a Blue Yeti or a Blue Snowball (both with a pop filter! ) are great ways to go. I use a Blue Yeti in my videos and for $100, I couldn't be happier with it. It works incredibly well, and is something I'd recommend to anybody who doesn't make a living off YouTube. (In that scenario, there are some higher quality mics and mic setups you can get, but they can cost upwind of $200 at a minimum.)

Video Card: Sapphire HD 7970 Vapor-X GHz Edition 6GB GDDR5

CPU: AMD FX 8350 8 Core 4.0GHz Processor 16MB Total Cache

Hard Drive: 600GB 10K RPM, 1TB 10K RPM for recording

Motherboard: Crosshair V Formula

Headset: Sennheiser PC 350

Microphone: Blue Snowball

Mic Stand: RØDE PSA1

Pop Filter: Nady MPF-6 6-Inch Clamp On

Webcam: Logitech HD Pro Webcam C920

Memory: 16GB DDR3 RAM

Case: CoolMaster 922 HAF

Power Supply: CoolMaster Silent Pro 1000W