G-Tech Hard Drive cannot be seen by Disk Utility

i have a G-Tech 1TB hard drive. it's a great drive that i've had for a while - and until now i've never had a problem with it. unfortunately the firwire cord was disconnected while iphoto was in use. now the drive cannot be seen by disk utility and i'm stuck. is it this easy to destroy your precious files and photos? Can someone help? Once it's repaired (look to the heavens), can someone suggest a more idiot proof method of managing external hard drives?