I have been looking for an answer myslef and have seen only 2 others having this problem. I don't see any of our NT server nor our 2 Appleshare IP servers or get LPAD to work. However, I get e-mail so the network is available.
I've found a similar problem on my OS X set up at work, except that only one machine is visible under AFP file servers ( a b/w G3 350 running MacOS 9). The machine I'm really interested in connecting to is an old PowerTower Pro running SUSE Linux for PowerPC, with netatalk (ie AppleTalk for Linux). The whole network is clearly visible and works well under MacOS 9.
The only way I was able to connect to the Linux box was by entering its IP address in the Connect to Server dialog. This mounted the server - but none of the directories or files were visible to the Finder.
It gets interesting now. I opened a terminal window, and was able to navigate to the server and see most (but not all) of the 'invisible' files. Very strange.
My guess is that the problem is related to the way the OS X Finder hides UNIX-ish files.
My machine at work is as follows:
G4 450 with 384MB RAM, and a 20GB hard drive divided into two partitions (OS 9 and OS X respectively). Also two video cards - the original, plus another ATI card that works beautifully with my second monitor under OS X.
Since my last post, I've looked into the problem a little more. It's basically quite simple, I think - OS X only supports AFP over IP. Which doesn't explain my experience in the command line - perhaps that's just because the feature is partially implemented? I'm guessing. At any rate it's an issue that Apple are well aware of.
To see the other Macs on your network, just make sure that the 'Enable clients to share over TCP/IP' option is checked in the file Sharing control panel. Any servers running Appleshare IP or MacOS X Server should be fine. As for NT - I guess Services For Macintosh doesn't use TCP/IP, at least by default. I believe there are AFP IP servers for Windows NT/2000, though.
None of which helps me much with my Linux box. Hm. Anyone know anything about NFS?