Well the first step will be to recreate the files under /dev/vg01. Look at the files under /dev/vg00 for an example of what is necessary. You will need a device file called "group", and two device files for each logical volume (one "r" (raw, or character) file and one "cooked" (block) device file).
'man mksf" for details.
Once you have the device files recreated, a vgscan will probably get you back on track. You may need to hand-edit your /etc/fstab file to get all your file systems mounted again...