I hate to tell you this but unless your mac did a quick format which would have only taken a few seconds your data is gone. I have done my fair share of data recoveries back when I worked as a forensics tech and I can tell you it is a slow process to get your data back. Unfortunately if you want to try you will only get one shot at it with most people. I no longer have current tools and I am no longer bonded or I would offer to do it for you. If you use a service, which is your best bet, expect it to cost at a minimum 300-700 dollars. If you decide to trust it to a local person or try yourself it will be cheaper, but the likelyhood of recovering good data goes down signifigantly.
make certain they do the following things:
1) Mount the drive read only
2) Clone the remaining filesystem to a separate device before trying recovery.
This takes all the data on the drive in its binary (1 and 0) form and lets the recovering computer play with it to recover the most files and not touch the original data so you can have more than one shot at the recovery.
There will be people here who suggest one application or another, just be aware that experience is part of the recovery process.
Robert K. "Kelly" Brumbelow
In Inquirer's class at Grace Presbyterian (PCA) Cedartown, GA
Cedartown, Georgia
Dear Lord and Father of mankind, Forgive our foolish ways;
Reclothe us in our rightful mind, In purer lives Thy service find,
In deeper reverence, praise. - John Greenleaf Whittier 1807-1892
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