I just dug up my old Powermac 7500/100- my first computer ever- and because I'm more interested in the files that are on it than in the computer itself, I've decided to file share most of the hard drive's contents to my iBook G4. (The Powermac has like a 150 MB hard disk.)
I'm trying to put the old boy on my home network, which has been a bit difficult. Is there any other practical way I can connect the two computers together so that I can transfer files from one to the other?
Thanks in advance. 
Apple has discontinued support for "Classic AppleTalk," but that doesn't mean you can't share files between older Macs and newer OSX Macs.
This all presumes you have the proper Ethernet cables, adapters, switch(es) and router you need to physically connect your Macs. If not, you'll need to take a trip to your local Apple Store, Best Buy or CompUseless.
1) You need to be running Mac OS 8.5 or later on your 7200. This might also mean increasing the RAM on the machine -- I think 8.5 requires at least 32 MB RAM.
2) On the 7200, make AppleTalk active via Ethernet. Use the AppleTalk control panel (under the Apple menu) and Connect via: [Ethernet]. Quit the AppleTalk control panel.
3) On the 7200, enable File Sharing. Use the File Sharing control panel and click the box for "Turn File Sharing on." Check the box underneath that says "Enable users to connect via TCP/IP." Quit the File Sharing control panel.
4) On the 7200, configure TCP/IP. Use the TCP/IP control panel and configure the settings to match the rest of your network. If you're using a router to assign IP addresses, then Configure: [using DHCP]. If you're setting addresses manually, then Configure: [manually] and fill in the boxes in the control panel with IP address, subnet mask, etc., that work with your home network. [If you need more help configuring manually, private message me.] Quit the File Sharing control panel.
5) On the 7200, share your hard drive. Click once on your hard drive icon. Go to the File menu and select Get Info > Sharing. In the Info window, check the box that says "Share this item and its contents." Allow all users to read and write. Close the info box.
6) On the iBook, go to the Apple menu and select System Preferences, then Network. Double-click on the "Ethernet" option. Check TCP/IP settings to ensure compatibility with the 7200. Click the "Appletalk" tab, and check the box that says "Make AppleTalk active."
You should now be able to connect to either Mac from the other using the Chooser (on the 7200), the Network icon in the sidebar of your Finder window (OS X), or using the Go menu on the OSX menubar (select "connect to server" and follow instructions from there.)
I hope I haven't left anything out -- hopefully other members can set us straight if I did.
Good luck!