Wow, I'm so psyched. My printer works!
For me, the winning combination was to follow the web page suggested by Bryan, but to install the ppd file that Simone created, and then to use http://localhost:631 as suggested by Marc to do the printer administration.
The one trick was that in the CUPS web interface, there was no way of figuring out the printer location. There was no device scanning feature or suggested locations for it. But since I had already tried using Gnome's printer GUI, I knew my printer was at /dev/usb/lp0.
Just before posting here I successfully printed out a CUPS test page, and also a page from some random web site in Firefox.
Thanks to everyone for making a potentially horrific task and making it very easy. Installing this printer was just slighly less painful than getting my Palm Pilot to connect.
Dave