Folder structure for simple category/file management

Hi there.

Is there an addon or upgrade, that allows to easily create huge folder structures (categories) in copy-paste style?
(Multiple folders for technical documents to dozens of machines each with multiple versions)

I´d prefer to do it via ftp – if possible.

but in
..wp-content / uploads / download-manager-files
there is merely a list of the uploades files.

Many thanks, K