because reading posts on here about similar situations arnt quite the same as mine and the fixes go off on a tangent.
I have a 3 tb seagate goflex that 1 day decided not to work any more

connecting it to pc gives the old 'must format the drive to continue' which i obviosly dont want to do
drive shows as raw

im assuming i should use testdisk to get my files back?
now the problem is that testdisk doesnt let me browse to backup files.
instead it awkwardly wants to look at partitions
then tells me its too small etc:
The harddisk seems too small!
The following partition can't be recovered:
how do i repair the boot sector so the drive works properly?
how do i recover the partition?
how do i backup my files?
theres no instructions so you just go round in circles not getting anywhere

plus the program is ridiculously slow,1000s of hours left,been on for 2 days etc

help