If you use the current version (v7.x) of Netscape, click on File,
then click on EmptyTrash. Simple.
If you use Lookout or Lookout Expressly, I think you need permission
from Bill Gates to delete stuff that John Ashcroft hasn't yet read.
{Note to Michael Hayden: that's a joke, OK?}
Nowhere. Are you attempting to recover the space they occupied or what?
If youre worried about someone finding the text in the file or
recovering the drive space just compact folders.