It appears that Shapeways has reorganized its website to make items easier to find. Here is a link to the "Aircraft" index page, where you can filter by scale, type, era, and country. Accessories such as engines are also included. There's even a Norden bombsight!
https://www.shapeways.com/marketplace/miniatures/aircraft/
There are also index pages for sci-fi, ships, vehicles, trains, and other items.
Note: I have no connection to Shapeways or any of the designers whose work is sold there.