Are there any free tools to wipe the user contents of a Macintosh running OS X v10.5.8 to keep the operating system and software products installed but remove any user data for selling the computer to another party?
If you want to be completely sure that all traces of your data is removed, both of the "prep for sale" guides (here and here) that I came across recommended wiping your machine's drive and reinstalling OS X. The good news is that you can accomplish this without purchasing or installing any additional software - just back up your data and use Disk Utility to wipe the drive.
Apple Toolbox's guide recommmends:
However, the steps here will not leave your existing software in place.
If you're interested in leaving the software and OS X in place, deleting all of your data files, and use Disk Utility to wipe the free disk space. Steps from Apple Support:
You may also want to create a new admin user, delete your old account(s), and run the Disk Utility routine to erase free space used by your account(s).
You can go a really long way by creating a new admin user account and then using it to delete all the existing user accounts, including deleting their home directories. Then I might delete any existing network "locations" in
I guess there could still be some traces left in
...Hmm. The more I think about how complicated this problem is, the less I would trust any tool to do a good job of it. I think you really need to just "nuke and repave".