It depends on how important the data is and why was it not backed up. If it is valuable data then I would have a go at it with Fruit Bats suggestion but a tricky operation, you could possibly ask your local PC shop if they would be prepared to do it. With nothing more to lose I would open it up, connect it and see if the motor is working before accepting the diagnosis as final. You may even be able to fiddle with it and get it running for long enough to copy you data (if you are very lucky). If in fact the motor does appear to be working then come back here as some wiser members can give good advice on data recovery.

Sanap & rdave, changing the motor is fairly easy, even I can do that. Motors rarely fail it is normally the electronics. If you connect it can you hear it spin up, a whirring sound. If not then make sure it has power to it. Changing the motor should be a 15min job for a PC shop with the right tools. If you have another Seagate drive to take a motor from I will tell you how to do it step by step

Hi Chaps - I'm an Indentured Instrument Engineer and used to work in Tilbury Power Station years ago! I have a 200gb Seagate drive from an old (2008?) Dell laptop (SATA) and a couple of older 3 1/2" desktop HDD's (not Seagate).

Surely it's more likely to be the circuitry that's failed rather than the motor - which has only one moving part. On the Seagate HDD you can see the 3 (tiny) bare copper feeds into the motor so if you know the voltage you could bypass the board and run the motor as a test. If the motor runs then it's the board (easily removed).

On the 3.5 desktop HDD's the motors are built into the stack so you'll have to split it open to get it out - exposing the stack. They are assembled in a Class 1 Cleanroom (absolutely NO dust present) as the gap between the heads and discs is a few Microns. Tricky if it's opened. The 3.5 HDD's are different models - one has a ribbon cable to the motor (easy to put power on) but the other is sunk into a groove in the casing but removing the circuit board gives access to the connections to test the motor.