Your second article had some relevant info but unless I'm missing something major Kinko's doesn't support IP printing.
Turns out it's not IP printing at all, it's good old AppleTalk.
1) Turn on AppleTalk in Network Prefpanel/Ethernet port.
2) Open Print Center in Applications/Utilities
3) Select toolbar icon "Add"
4) Select "Appletalk" from dropdown menu
5) Select "Local AppleTalk zone" in "AppleTalk network" dropdown menu
And there you see a list of printers. Whether the printer's AppleTalk ID is understandable seems to depend on the configuration, I found the one I wanted by sheer cussed experimentation. But at another Kinko's the printer names matched the machine model. So go figure.