Got it working!!!!!!
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Okay, so after three hours of talking to D-Link Tech support... nothing changed. They even remotely accessed the router, configured a bunch of stuff and still nothing.
Reinvented, I took some of the same steps you listed above.
Updated Router firmware to 1.15
Plugged in my ethernet cable to the Mac and logged into the router
Made a DHCP reservation
Ensured 2.4 Ghz was set
Changed from mixed 802.11 to 802.11g and 802.11b Only
Disabled Auto Channel Scan
Set wireless channel to 11
Enabled WEP encryption
Disabled Wi-Fi Protected Set Up
Manually configured IP addresses for the router and the Mac in the network settings tab on the Powerbook
Saved settings and re-booted router
Logged into the network on the Mac by putting a dollar sign in front of the password
...And ta-da...
It connected.
So after all this time, the Powerbook is wirelessly connected to the router and accessing everything on-line.
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