I have a home network and recently added a VISTA machine. It can see the printer on the network but when I go to connect to the printer, I get an access authorization error.

I have tried all the obvious things..printer is in share mode, everything I am aware of has permission to share; I've loaded the Vista driver, etc. I have followed all the lame obvious help provided by Microsoft

Any ideas?

Have you created an account on the Vista PC which is the same as the one on the XP machine? If not create it or just enable the Guest account to access printer.