So I dont have to build an OS from scratch each time I want to provision a machine I've been using a Syspreped image, copying it and then renaming it using the VMware console. The procedure is as follows:
Create your Syspreped OS and upload it to a datastore on VMware ESXi/Hypervisor in to a folder called something like 'Master Images'.
Create a copy of the Syspreped image: create a new folder for your new VM with a sensible name then copy just the VMDK file from the Sysprep image to the new folder.
Use the steps 5 to 7 in the following Vmware KB article to rename the VMDK file to something more sensible:
If that link has died since I made this post, the steps were as follows:
5. Open a console to the ESX or ESXi host. For more information, see Unable to connect to an ESX host using Secure Shell (SSH) (1003807) or Using Tech Support Mode in ESXi 4.1 (1017910).
6. Navigate to the directory containing the virtual machine. For example: cd /vmfs/volumes/DatastoreName/originalname/.
7. Rename the virtual disk (VMDK) files using the vmkfstools -E command.
vmkfstools -E "originalname.vmdk" "newname.vmdk"
I've tested this on ESXi 4.1.0 and Hypervisor (ESXi 5).
