http://docs.fedoraproject.org/en-
US/Fedora/18/html/Installation_Guide/Making_Minimal_Boot_Media.html#Making_Minimal_Boot_Media-UEFI
3.3.1 refers to a efidisk.img file in the images/ directory on the Fedora 18 installation DVD. This file doesn't exist. There is an efiboot.img, but I'm not sure if that's what should be referenced instead.
https://bugzilla.redhat.com/show_bug.cgi?id=904292
Chris Murphy