.ipsw files PLEASE HELP

[theyknow]

I can't seem to find them, I know this has been posted many times before.

I'm currently running on OS X Lion v10.7.3

I've tried so far:

1.(user name)/Library/iTunes/(Then just a plug-ins folder with nothing in it)

2.Home Folder/Library/Application Support/(Then Nothing iPhone or iTunes related)

3.Finder - Search ".ipsw" in 'This Mac' and 'All My Files'

I should have a few .ipsw files on here, I've synced under a few different iPhone names.

I'm the Admin of this MacBook, and no one else uses it.