Where do deleted iPhoto file "go" . . .

[RHPConsult]

Soliciting some (more) iPhoto advice for my daughter?

Thanks to helpful advice/opinions from several members of this distinguished assemblage over the past month or so, she's now the owner/operator of a very smoothly functioning G4 flat-panel and a 23" iMacIntel . . . all networked (Airport) at her home with an HP AIO, and both backed-up safe and sound to an external 1TB MercuryElite HD. Both running Snow Leopard.

In the process she has also cleaned-up her iPhoto Library . . . down from 6000+ items (including duplicates) to about 4300. She asks me a question for which I seem, but only hazily, to recall a TeeEss thread of a couple of years ago on cleaning-up excess iPhoto files, beyond just "deleting" the dups. Isn't there some Library/cache/whatever where those now unnecessary photo-flies have been stashed? Do I remember that correctly?

Do they have to be fully "hosed", somehow, in some way, so to clean-up your hard drive . . . really?

Thanks.

[sandbox]

FYI
iPhoto cache files stored in user/library/caches
plist file locations com.apple.iphoto.plist in /users/library/preferences/
thumbnail images /thumb.data

there were some problems between iPhoto and Mail cache files in years gone by


to rebuild.....
iPhoto 6 and later: Rebuilding the iPhoto library

http://support.apple.com/kb/HT2638