Print Server to USB HUB?

No, each printer would need its own IP address, meaning each would need its own printserver.

Well, you're right about IPs of course, but your computer will specify a printer by IP (the print server's) and port (also the print server's).

The multiport print server works by setting up each port individually, when you set up the printer, you determine which USB port the printer is actually on. When you go to set up that printer on a computer, you specify the port on the printserver where the printer you're interested in is to be found. A single port print server doesn't typically come with this ability - you only specify the IP address of the printer. If yours allows you to go further and denote a specific port, you might be able to do it.