We've put together instructions for extracting the components of ESXi embedded in the installable ISO image for people that would like to use other install options, such as PXE booting and flash drives.
lance
Do you have it running (i.e. with VMs ) from a PXE source? If you're looking to do a PXE install, you can just take the tgz files from the root of the CD.
The build version is the one in install.tgz. The first image you find is used only for the install. It may boot, but is not necessarily the one you want.