These are some common commands that are used when managing LVM devices.
Volume Groups
Create a volume group: vgcreate vg0 /dev/sda3 [/dev/sdb /dev/sdc /dev/sdd ...]
Logical Volumes
Create a LV: lvcreate -n LV-NAME -L 30G VG-NAME
Delete a LV: lvremove -n LV-NAME VG-NAME