If it is RAID 0 (striping), unfortunately, there is nothing you can do to save your data. There is no data redundancy in a RAID 0 setup.
If it is RAID 1 (mirroring), then you just hook it up to another computer and try to access the data.
I'm guessing you have a striping setup though from the sounds of it. If the drive is in fact going bad, and you have them striped, then you basically need to replace the bad drive and start over.
If you do have a striping setup, just connect the drives back up and run a hard drive diagnostic. Normally I would suggest against doing it because the diagnostic could end up killing the drive. But, if you have the drives striped, then you can't salvage your data anyway. So at least if you do a hard drive diagnostic on both of your drives, you can see if the drive is actually going bad or if it is another problem.
To do a diagnostic, click on the link in my signature that corresponds to your hard drive brand. From there you will follow the instructions on creating a bootable diagnostics disk. Create the disk, then boot to it and run the diagnostic to see if your drive(s) are bad.
If you need help with any of the steps, just let me know.
Hope that helps!
