With only a couple days to go, it looks like Amazon is sending out emails to those that signed up to inform them of the purchase process for the upcoming NES Classic Edition.
As expected, the NES Classic Edition will be offered in limited quantities on release day. According to the email, Amazon will begin selling the console starting at 2pm PT. Those ordering will not be able to utilize the expedited "1-Click" ordering option and will have to go through the manual purchase process. Although demand will be high, they will make additional announcements whenever the unit comes back in stock.
Amazon is the first retailer to publicly outline its purchase process in the US. The official Nintendo website does also list Best Buy and Target as supported merchants, but neither have offered a pre-order process or outline thus far. Those in the UK that have secured their unit via a pre-order can rest easy, while those in the US might be in for quite the surprise come Friday.