Ubuntu :: Cannot Locate Filesystem After Trying To Reinstall

I was trying to backup everything, format/overwrite an partition to start with a fresh start after some annoying issues with my previous installation.

I had a perfectly fine working partition table and i chose to format partition
#1 (Ext4) partition (~50gb)
from the installation tool from the ubuntu live cd.
I had more partitions
#2 was ~5gbits swap
#3 was some unencrypted data(~20gb) (I think it was Ext3)
#4 was encrypted data (~150gb) (Ext4)
#5 unpartitioned data (~100gb)

So while doing this the installation failed somehow during the format of the disks, I tried testdisk but it couldn't locate the HDD nor any other program. When I look at my /dev it says this (from live cd):
root@ubuntu:/home/ubuntu# fdisk -l
root@ubuntu:/home/ubuntu#

Mount says:
root@ubuntu:/home/ubuntu# mount
aufs on / type aufs (rw)
none on /proc type proc (rw,noexec,nosuid,nodev)
none on /sys type sysfs (rw,noexec,nosuid,nodev)
udev on /dev type tmpfs (rw,mode=0755)
/dev/sr0 on /cdrom type iso9660 (rw) .....

/dev/sdxx doesn't even exist and this also doesn't seem to work:
root@ubuntu:/dev# ls -al | grep h
drwxr-xr-x 2 root root 3240 2010-01-12 00:16 char
crw-rw---- 1 root root 10, 228 2010-01-12 00:14 hpet
crw-rw---- 1 root root 10, 56 2010-01-12 00:14 network_throughput
drwxrwxrwt 2 root root 140 2010-01-12 00:32 shm
crw-rw---- 1 root root 10, 231 2010-01-12 00:14 snapshot

I nearly have the idea there is no hdd in my pc while I am very sure it was here some hours ago. I didn't made it fall on something hard while running or something so all inside of the box should be just fine. I can't reach my keepassx file (stored inside the encrypted part) so I also can't log onto my workspace or anything, it is quite crippling currently.