Yeah, you'd want the PC I laid out above.
Mobo: Rampage IV Formula
CPU: Intel 3930K
RAM: 4x4GB of 1866+ DDR3
PSU: Corsair AX860i
Case: Fractal Arc Midi R2
CPU Cooler: Corsair H100i
Fans: 3xCorsair AF140 Quiet Editions to replace Fractal fans
SSD: Crucial M500 480GB or 960GB
Soundcard: Sound Blaster Z or Xonar Essence STX
Video cards: Two Titans
Alternatively, you could swap the CPU with a 3770K and a Gigabyte Z77X-UP7 motherboard, or MSI MPower. It'd be a bit cheaper, but definitely not as fast in video editing.
The Titans are great cards to have for additional editing power. Vegas prefers AMD, Premiere prefers NVIDIA. You can definitely use NVIDIA cards in Vegas though.
You can also get a nicer case, but it wouldn't do anything other than look prettier. This is important to people like me, but I definitely understand that not being a priority.
If you are needing someone to build it for you, I'd be more than happy to get it set up and running.