|If it isn't detected by the BIOS then it won't make any difference whether you use Windows or Linux because they both rely on the BIOS before the OS starts.|
The flashing light means very little, the circuitry within the enclosure could be doing anything when the light flashes.
External drives are usually just a standard harddrive housed inside an enclosure, so the next stage would be to see if you can dismantle the enclosure to get the drive out so that you can connect it directly to a computer. Do a Google search to see if anyone has ever taken apart the particular model of drive you have - unfortunately they are rarely made to be user-accessible, but someone may have done it.
Alternatively, as already mentioned, a commercial recovery service is the next option - expensive, but not as bad as it used to be.
"I've always been mad, I know I've been mad, like the most of us..." Pink Floyd