From apple:
This articles describes what to do if You Can't Eject a CD or DVD, or Open the Drive Tray.
Important: Make sure the disc is not in use. Quit all applications that are using files on the disc.
1. Place the computer in sleep mode.
2. Press the Media Eject key at the top-right corner of the keyboard.
3. If that doesn't work, drag the disc's icon to the Trash.
4. If that doesn't work, restart the computer, then hold down the mouse button.
5. To restart, choose Restart from the Apple menu.
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So when you say you are holding down the track pad, I think you should be holding down the trackpad button.
There were some notes at apple about using paperclips to force an ejection and here is a link for the powerbook:
http://docs.info.apple.com/article.html?artnum=88068
