It appears as though Amazon.com has decided to cease sales of the Nintendo 3DS and Nintendo Wii U on Amazon, although they will will fulfil orders from third-party suppliers.
This isn't the first time Amazon has had a disagreement with Nintendo, but there has been no real reason offered as to why sales of the platform stop being fulfilled by Amazon.
If you want to buy an Aqua Blue Nintendo 3DS it is currently being offered for $190.00 by the retailer super dooper, which is fulfilled by Amazon. Likewise, the same situation is applicable to the Nintendo Wii U
Amazon are sure to offer the platform again in the near future, as they are sure to be losing money through this dispute.
Source: Go Nintendo