Google Product Forums
Re: I accidentally deleted a whole folder of subscriptions!
Jun 26, 2012 11:49 AM
Posted in group:
Google Reader Forum
How Do I? :
Surely you at some point had downloaded a backup of all your subscriptions in Reader Settings / Import/Export ?
Other than that, besides hunting for stuff in your browser history,
check the Recently read/kept unread lists in GReader homepage, and the Trends page.