It depends on how you have your network configured and which MacOS you are talking about. For TCP/IP stuff, the Mac is basically identical to a PC. You can set static or DHCP IP addresses. They can use the same routers and switches and everything. Even wireless 802.11b ethernet is pretty much seamless.
Where they differ significantly is with platform-specific network services. Macs don't natively see Windows shares. They don't care about Windows workgroups or domains or WINS or the like. They can't generally use a printer that is only being shared through a Windows server or a Windows-specific print-spooler. All the above also goes for Novell networks.
That's not to say that you can't make a Mac work on a Windows or Novell network though. It just requires third-party software. DAVE for the Mac is an excellent Windows networking tool. It basically lets a Mac be a full member on a Windows network, alleviating pretty much all the above issues. The other route is to enable services for Macintosh on a Windows server, but that can make some admins get twitchy.
With Novell networking it's a little trickier. There is a Mac Novell client that you can buy, but I don't know how current it is. I'm pretty sure that if it is still available it only works with OS 9 and lower. To my knowledge, there is no Novell client for Mac OS X.
Then there is the inherent Mac networking. Just like Windows has its own platform-specific networking capabilities, so does the Mac. AppleTalk is the traditional method of Mac networking. It's just a protocol, just like TCP or NetBUI. Mac networking is inherently peer-to-peer, and AppleTalk is the communication. It runs on just about any network, even over IP, but some routers may need to be configured to handle AppleTalk packets. Segmenting an AppleTalk network to create "Zones" requires, obviously, a router or server that can define AppleTalk zones. It may sound confusing, but it's really pretty seamless.
Network printing is also usually peer-to-peer. Each computer on the network directly talks to a printer, no print servers. You can either use a printer with AppleTalk capability, or it can be pretty much any TCP/IP printer since modern Macs can do LPR. Just go to configure a new printer, type in the IP address, pick a specific or generic print driver, and you're good to go.
OS X is throwing a curve ball into traditional Mac networking. Because it is a unix-based OS, it features all the TCP/IP capabilities of a unix box, including ports that you need to be sure are closed. You can configure it for SAMBA sharing, just like a Linux box (though DAVE is still more full-featured). Apple is even trying to kill off AppleTalk and go strictly TCP/IP. That caused a major protest though because it kills backwards compatability with established Mac environments. AppleTalk is in OS X, and that's a good thing for now.
In general, the Mac is fine on an agnostic network. When you start trying to ask it to be a seamless Windows box, then you've got issues.
