The Xbox One X is not yet on sale. Microsoft has given a launch date — Nov. 7 — but pre-orders are not yet being accepted. When they are, supplies are probably going to be scarce.
Following are the pre-order sites for the major retailers in the United States. Some feature email sign-ups where you can be notified by the retailer when the pre-orders are live.
One point to make: According to the fine print on Microsoft's site, the Xbox One X is not yet approved for sale by the FCC. This probably explains why we have a price and a launch date but no pre-orders. (This also is not unusual; the first PlayStation 4 was announced in February 2013 and approved by the FCC the following July.)
Anyway, here are the official product listing pages at some of the biggest retailers:
Check back here when pre-orders are announced.
Update: Microsoft’s Albert Penello said pre-orders will take place later on in the year; this week is about launch date and price only.