It's already in ROM on some H/PC Pro devices. Check Start -> Settings -> Control Panel -> System to see if the installed applications are version 3.0 or 3.01 (not 3.1). See this page for more details:
Thanks, that has almost everything I need. MicroSoft still has the Plus! and Power Toys downloads, so all I need are the CE Services CD(?) original IBM CD, and Entertainment Pack.
You can get Plus and PowerToys from the download centre here, and if you search the download centre for "ISO" you may find something of interest (be it the 2.00 version)