Hello Timor,
I see no reason why you wouldn’t be able to purchase a fibre channel disk array and initially connect it to only your server. You could then later, as you said, purchase a switch and connect all of your work stations to the storage. At that point, you would need some form of SAN management software. Here at CommandSoft, we have just released FibreJet for Windows XP. Please contact us if you have any further questions.
https://www.commandsoft.com