QEII Student IT
Hi! Have you verified that other wireless devices do get a strong signal at home? If not, that might be worth verifying. Is the iBook's ability to get a signal in your home affected by whether or not the iBook is right next to the router, or in another room? I have a brick house and had problems when the router was downstairs, but it improved when I moved it to the main floor.
I don't know what kind of router you have, but updating to the latest firmware is always a good idea and could potentially affect performance. Also, do you have wireless phones in your house? Sometimes they can affect wireless performance, and so changing the wireless to a different channel can help.