The drive may be dead...
First, go to seagate.com (they own maxtor now)
Go the the downloads section, there you can download Dianostic utilities like "Seatools" and a file recovery program.
OR IF THAT DOESN'T WORK
You can take it to a file recovery service to get the files off the drive. FYI using this service can cost from $80 up to hundreds (You'll have to get a quote from them)