I was struggling till I followed the instructions in this other discussion:
http://macosx.com/forums/hardware-peripherals/245823-dell-3000-cn-printer.html
Just tried it and it worked for me. (Running Mac OS X 10.4.11)
b.
The second stage file has moved. I found it here:
http://www.openprinting.org/download/printdriver/macosx/old/
Full URL:
http://www.openprinting.org/download/printdriver/macosx/old/hpijs-foomatic-2.0.2.ppc.dmg
Haven't tried the process yet and not sure if it'll help me as I'm trying to print...