Probably not if you've used the drive at all since you deleted the folder. However, if you want to try, this is what I would do.
1. Turn off your Mac immediately. Do not use the Mac at all until you have done the recovery. Every little thing you do with the Mac could potentially write something over the data you're trying to recover. Do not start the Mac up normally again until you've run the recovery.
2. Get another Mac with a FireWire port and run a FireWire cable from the FireWire port on your Mac to the FireWire port on the other Mac. Make sure no other FireWire devices are connected to either Mac.
3. Start up your Mac with the 'T' key held down on the keyboard until you see a FireWire symbol bouncing around on the screen like a screen saver.
4. Your Mac's hard drive should show up on the second Mac's Desktop.
5. Run Data Rescue, by Prosoft Engineering on your Mac's hard drive. Do the slow, thorough scan. See what can be recovered.