This may be just what you need:
https://www.hardware-revolution.com/best-mainstream-workstation-reliable-powerful-quiet/
You’ll notice that the author offers to babysit your efforts, and for free. I join the DIY advice here — you could save not just hundreds but thousands, not to mention knowing much better the horse you will be riding and being more fluent when it comes to upgrades or repairs.
The high-end workstation build alternatives, which will be organized around the new dual xeon E5 26xx line, is promised for pretty soon, but could proves weeks or even months off, let me warn you. But the current one is fresh and should be an improvement on the best being discussed. The matter of video cards is special to the editing application and made need some further advice.
(Haven’t yet managed to read all the posts in this thread, forgive me if I’m not the first with this link. Can’t find the “flat view” button)