Are you using OS 9, since you're mentioning the File Sharing control panel? If you've set up passwords and allowed sharing, just open Chooser from the Apple Menu, select AppleShare and see if the other Mac is there, and if so, connect to it. There might be a Network Browser app somewhere on the disk that you could use too.
If this is OS X, go to Finder and hit Apple+K, then type the address as explained in the Sharing pane of your System Preferences.