Linux disk diagnositic tools?

[Karl Krasnowsky]

In an attempt to repartition my secondary drive last night, parted 1.2x
reported disk read errors when I attempted to create a linux-swap
partition.
Events leading up to this:
1) After removing old partitions, created a 6g extended partition - worked
fine
2) created a 1g logical partition (ext2) - worked fine
3) attempted to create the 128m linux-swap partition - failed miserably
with multiple disk read errors.

Any advise on what I should do at this point? Obviously I'd rather not
have to replace the disk if I can help it.

thanks for any help.
Karl