Add disk using vmware ( if your expanding a disk i suppose you know how to add one )

ls /sys/class/scsi_host ( to check wich scsi id the host has )

echo “- – -” > /sys/class/scsi_host/host#/scan ( host scsi id )
fdisk -l
tail -f /var/log/message ( to check if the disk was added succesfully )

formating the disk and adding it to the lvm disk : http://www.schalley.eu/2009/12/09/extend-disk-lvm-linux/