Another Dedicated server question. FDISK

I have dual 120 GB drives with Raid installed and I need to be able to use both disks. Looking through the Godaddy help files for the server it says that i must fdisk the 2nd drive - which in reality should be no problem.

I tried the disk name they gave me ( /dev/sdb )- it doesn't appear to be a drive name or I just can't fdisk to it. So I called up fdisk and it gave me:

Usage: fdisk [-l] [-b SSZ] [-u] device
E.g.: fdisk /dev/hda (for the first IDE disk)
or: fdisk /dev/sdc (for the third SCSI disk)
or: fdisk /dev/eda (for the first PS/2 ESDI drive)
or: fdisk /dev/rd/c0d0 or: fdisk /dev/ida/c0d0 (for RAID devices)

Trying to call up what should be the second disk (here called the third?)

I got this error:

Unable to open /dev/sdc

Does anyone with experience on a dedicated server have some suggestions that would help me set the 2nd drive up?