I'm an instructor at a small technical college and the only Mac user in my department. Our network is heavy on Windows, as expected, with some UNIX. Our Graphic Design department uses Macs, of course.
Anyway, our printers are HP LaserJets shared over the network. They support all types of connections, including Appletalk and TCP/IP. Under OS X, the HP PPDs are only available using LPR (TCP/IP) printing and I couldn't seem to get that working. I had to use Appletalk instead which only allowed me to print Postscript. (I try to print text, as from BBedit and get an error message.)
Just this afternoon, however, I figured out how to connect to the printers using TCP/IP so I now have full use of the HP PPDs.
From the Print Center, select Add Printer and from the connection type pulldown list choose LPR Printers using IP. Enter the IP address (or IP printer name if it's registered) and uncheck the Use Default Queue on Server box. In the queue name field, enter in the name that you want to use for that printer. (Try not to use spaces. Use underscores instead.) Select the printer type from the pick list and click on Add. The printer will appear in your printer list and be ready to go.
My problem was that I was trying to use the default queue rather than setting up my own queue name. (Ironically, this came to me while teaching a group of students how to set up LPR printing in Windows.)
Mac OS X Hints
http://hints.macworld.com/article.php?story=20010823002548107