Find Host from VM

Seems I have several lost sheep.

Is there a way with PowerCLI (or any other way) to get host information from a VM? 

I found out my client has several independent VM Hosts not in vCenter.  They also have networked "production in use" servers on Workstation and old VM Server.  I need to find those hosts.  In a company of this size, it would be the best approach to pull from VM (if possible) to find the host.

Thanks,

Boston TechGuy