> Aminet - as there are many files there to browse that work with MorphOS

...or http://morphos.aminet.net to filter for MorphOS-specific (and generic) files.

> MorphOS Files - for native coded MorphOS utilities, appplications, games, etc.

Although that site is still linked from MorphZone as the official repository, it's worth noting that it has been abandoned almost a year ago due to the maintainer leaving MorphOS. The site still works, but last upload was in January 2016, which could lead to the wrong conclusion there was no software written/ported for MorphOS since.
Following the demise of the MorphOS Files site, the MorphOS Storage site has been established half a year ago.