The Amiga productions will be available at the main site as soon as possible. I know that the demo and intro from Up Rough was made for the Amiga, but I'm unsure about some of the others. In the meantime, you can always check for these prods at Pouet.net. Those made by Up Rough is available there.

Edit: Two of the Amiga prods (don't think there were more than two) are available for download at Classicamiga.com. Head over there now!