I think you are looking under the public_html/admin/plugins/forum folder - or as it's packaged in the archive forum/admin.
That is the admin scripts and I am referrng to the root folder of the plugin supplied archive. The archive is not restored under your public_html folder.
You may want to refer to the additional detail and graphic illustration
here
Geeklog components by PortalParts -- www.portalparts.com