Sounds like a dodgy WiFi device on your laptop to me. Is it internal, or a "plug in"?
If it's internal, try a scan for wireless networks (how you do that depends a bit on the software you're using).
If it's external and you have a different card, try that.
If neither of those works, download Network Stumbler and see what it finds. That's not what it's designed for, but it does quite a good job at it. If that says "No Wireless device detected", you know what's up. If it finds your network and others, then the problem is in the setup of your wireless network.