I recently installed a clean install of FC3 with the root partition under LVM2. I had a secondary hard drive (dev/hdb) formatted as ext3 that I migrated all the data off. I attempted to add it to the volume group and created a new logical volume. Here are the steps I performed.

1) pvcreate /dev/hdb
2) vgextend VolGroup00 /dev/hdb
3) lvcreate -L+50G -nLogVol02 VolGroup00

When I attempt to mount the volume, I receive the following error:

mount -t ext3 /dev/VolGroup00/LogVol02 /linuxbackup
mount: wrong fs type, bad option, bad superblock on /dev/VolGroup00/LogVol02,
or too many mounted file systems

a file system check produces the following:

/sbin/fsck -n /dev/VolGroup00/LogVol02
fsck 1.35 (28-Feb-2004)
e2fsck 1.35 (28-Feb-2004)
Couldn't find ext2 superblock, trying backup blocks...
fsck.ext3: Bad magic number in super-block while trying to open /dev/VolGroup00/LogVol02

The superblock could not be read or does not describe a correct ext2
filesystem. If the device is valid and it really contains an ext2
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
e2fsck -b 8193 <device>

What step have I missed in the process?

PVDisplay:
--- Physical volume ---
PV Name /dev/hda2
VG Name VolGroup00
PV Size 153.28 GB / not usable 0
Allocatable yes (but full)
PE Size (KByte) 32768
Total PE 4905
Free PE 0
Allocated PE 4905
PV UUID Y0G9hy-yWoX-lqVe-2nI6-euGH-9EiI-eEmDT2

--- Physical volume ---
PV Name /dev/hdb
VG Name VolGroup00
PV Size 74.50 GB / not usable 0
Allocatable yes
PE Size (KByte) 32768
Total PE 2384
Free PE 785
Allocated PE 1599
PV UUID nnuRnA-FrOY-n4Zh-Isdj-uqWc-wuCY-yiK7E8

LVDisplay:
--- Logical volume ---
LV Name /dev/VolGroup00/LogVol00
VG Name VolGroup00
LV UUID 84RI4D-ZlZj-nH2N-b345-7pFE-jcx6-bQGqYP
LV Write Access read/write
LV Status available
# open 1
LV Size 152.25 GB
Current LE 4872
Segments 1
Allocation inherit
Read ahead sectors 0
Block device 253:0

--- Logical volume ---
LV Name /dev/VolGroup00/LogVol01
VG Name VolGroup00
LV UUID unpvC6-66im-Cxrt-JIaO-C3HY-6BvO-QZn8cI
LV Write Access read/write
LV Status available
# open 1
LV Size 1.00 GB
Current LE 32
Segments 1
Allocation inherit
Read ahead sectors 0
Block device 253:1

--- Logical volume ---
LV Name /dev/VolGroup00/LogVol02
VG Name VolGroup00
LV UUID wBc7tp-cLwX-q9vY-ysIa-UzZO-1MCe-1Eb5By
LV Write Access read/write
LV Status available
# open 0
LV Size 50.00 GB
Current LE 1600
Segments 2
Allocation inherit
Read ahead sectors 0
Block device 253:2