Jaxbrian
Workshop plans? Do you mean placement of tools? Because if you do it is really hard to give advice or follow plans as peoples machinery varies in quantity and size. Just figure out what works for you. Make the workshop flow. Your dusty needs to be accessible to lathe, saw bench, bandsaw, yadda yadda yadda.
If you mean plans the actual building itself look at your local suppliers online.
If you want it bad enough you will get it together.
Pete