Thanks so much for the reply. I went through the DWL setup again to detect the 524's SSID, and the DWL is seeing the SSID. In fact, when I go to the setup screen for the 524, it is telling me that the DWL is connected. I turned off all encryption and firewalls that I could find. It still didn't work, so I moved the DWL and the iMac into the same room with the 524.
The WAN address is showing up on the 524. The only odd thing I noticed is that the iMac stopped getting its IP address from the 524 and I needed to reset it. Of course, I did forget to turn it off last night so it had all night to lose that connection.
After surfing some other discussions on this website, I did turn on Appletalk on both computers.
All that, and still no luck. Once again, the 524 sees the DWL, and I can ping the DWL and the iMac successfully. From the iMac, I can ping the computer hardwired to the 524 (the G4), but not the IP address of the 524 itself (odd - doesn't the ping need to go through the router to get to the G4). Dlink thought there might be something wrong with DWL, but since it sees the SSID and replies to the pings from the G4 it must be doing something. Can you think of anything else?