http://www.xendesktopmaster.com/how-to-add-an-additional-local-disk-to-your-xenserver-5-5-host/

http://www.ruslansivak.com/2010/3/29/XenServer-55–Converting-Local-Storage-to-ext3-and-thereby-enabling-sparse-provisioning

http://www.schirmacher.de/display/INFO/How+to+add+additional+disks+to+XenServer+host

Adding removable drives

http://kiekeboe100.hoefman.be/blog/2009/06/attaching-disk-to-xenserver-guest/

http://everyrandom.com/blog/?p=89