The Nexus 6 is finally a thing you can buy without hammering the refresh button for hours on end. Right now you've got your choice of buying the 32GB Nexus 6 from Google Play or Motorola, but at long last there is stock on Amazon.
So, head over to the Amazon product page and you can get the blue or white Nexus 6 for the regular price of $649. If you are a Prime member, that includes free 2-day shipping. That's the best deal of any official option. This is coming direct from Amazon as well, no sketchy third-party marketplace sellers.
If you do buy from Amazon, be aware support might be slightly more annoying. If something goes wrong with a device purchased from Google Play or Motorola, they usually just swap it out. If you go to Motorola with a device purchased from Amazon, there's no telling how smoothly things will go.