Windows 7: Wireless Home Network Not detected!

Hi, I have a Toshiba Satellite L655-149 laptop.

There seems to be a problem with the wifi. Normally, when the ethernet cable is not connected it would show the available wireless networks (like any other laptop).

But now it does not detect any wireless networks including my home network and I am sitting right beside the router.
I tried pressing Fn+F8(buttons to enable or disable the wifi) but that function isnt working anymore.
Is there any other way to turn on the wifi?..or is it something wrong with the driver and the wireless LAN card in my laptop?
Thank You

Do you still see the wifi icon in systray (on bottom right of screen)? If so, does i look normal? Red cross in image?

Goto network center. Change adapter settings. Wireless adapater is still there and enabled?
Goto device manager, network adapters. All looks fine?

Yeah when the ethernet cable is not connected there is a symbol of a computer with a red X on it at the bottom right part of the screen. But when I click it, it displays No connections are available. So it does not detect my Home wireless network.
Please tell me how to go to network center and change the adapter settings.
I went to Device Manager and clicked on Network adapters. It shows just something called Fast Ethernet Controller. Nothing concerning wireless connections. Could that be because the wireless LAN driver isnt installed?

Fast Ethernet Controller is only listed there in device manager? That's for wired connection not wireless.
Goto control panel and search for "network". Now you find network centre

Yes only the Fast Ethernet Controller was listed in Device manager.
When I searched Network in control panel i got network and sharing Center. I went to that and I clicked on change adapter settings but I could only find Local Area Connection. No wireless adapters were displayed.

Did it ever work? You told me you cannot find any wireless network!!?
You can't even browse for a wireless network.

Toshiba Satellite L655 Windows 7 64 bits?

What type of wireless adapter is in laptop?

Do this: How to identify the built-in wireless lan card and the installed driver version with the Toshiba PC diagnostic tool.
What wireless lan adapter?

I ran the PC diagnostic tool. Under the Basic Information tab, for Network it just displays:
Atheros AR8152/8158 PCI-E Fast Ethernet Controller(NDIS 6.20) version=1.0.2.43 MAC Address=00:26:6C:78:C6:C1

Nothing on the wireless adapter.