Gaming Build around $1000 (or prebuilt?)

Hello, all. I want a new gaming PC (primarily WoW). I built my current PC 7 years ago and updated components about 3 years ago, but I confess it was a bit nerve-wracking. I'm not looking forward to matching all million processor pins to the right socket, deciding which heatsink or cooling system is adequate, and trying to plug USB cables into cramped case with ambiguous diagrams and instructions. If there is a comparable decent prebuilt or partially prebuilt system, it would be attractive. Nevertheless if there is a significant bang-for-buck advantage (like over 10%), I'll put it all together.

I've never unlocked cores or OC'd but if turning it on is simple enough (like in BIOS startup) and heat isn't an issue I'm willing to give it a try. I've also never used liquid cooling but am also willing to try if required. Reading hundreds of posts I'm concerned that I won't match adequate cooling with my chips and video card if I mix and match. I ask advice from all you far-more-experienced builders!

OK, here we go: Budget $1000. Bundles ok. All components should have clear, unambiguous instructions and diagrams (preferably also available on web instead of looking at a 4-inch manual with a magnifying glass).  

No monitor, mouse, or keyboard.

OS--Need Win7, I'm not a student.

MOBO--I can't follow which chipset and buses are best, current, or outdated. Your help, please?

CPU--Slight preference for AMD over Intel. (Again, after all the charts and benchmarks I'm overwhelmed with data! 4 cores, 6 cores, 8 cores?)

CASE--Full tower--I need the space inside if my large Western fingers are going to make the wiring connections.  

VIDEO--SLI- or Crossfire-capable, but only one good (max out WoW) card necessary at this time.

RAM--8 Gb RAM.

HD--1 Tb should be ok. I've been reading about a separate SSD as boot drive. Good idea or unnecessary complication?

POWER SUPPLY: Your choice, but vendor should have easy return policy. I've had more trouble with these than any single component.

Thanks so much in advance, everyone!