Mac Forum / Applications / Mac Applications / December 2007

My first suggestion is that you should use the software with which
you've been diligently keeping backups to restore the most recent one.
This is really the best option for someone with limited funds, because
the time or expense involved in getting your files back when you don't
have a backup can dwarf the cost of doing it right.

But I suppose you're asking here because you didn't do that.

There are a fair number of services and packages that may have some
success at recovering files. You should pick one that makes you feel
comfortable by searching Google for terms such as mac, file, and
recovery. I found, for example, this:

<http://www.datarecoverymac.com/>

Never heard of it before; have no idea if it's any good. The page,
frankly, doesn't give me warm fuzzies.

You *should* have a copy of TechTool Pro. It's one of the packages to
which I think every Mac user should ensure they have access. That *can*
do some file recovery, although it's much more effective if you've had
it running with that intent ahead of time. It's still got a shot and
since you should have it on general principle the cost of trying it is
effectively $0.

It's very important that until you actually try to recover the data, you
do as little with that disk as possible. You're helped in this case in
that it's an external drive and (based on your phrasing) probably not
your boot drive. That means no swap files and cache files potentially
reusing the space your deleted files take up.

Google for "Data Rescue."