Hi Sue.
I had the same problems with setting up my X-Box 360 for wireless, but it is pretty easy once you know how

Get a blank pen/flash drive and plug it in any USB socket on your PC.
Then click on start, then my network places, then 'set up a wireless network for a home or small office'.
Then click 'next'. You should see two options.
The one you want is the 'add computers or devices to the '????????' network.
The question marks meaning it should have your network name there.
Then click next and save to your flash drive.
Then put the pen/flash drive in the USB socket on the XBox 360, switch on and navigate to the far right to the 'system' page and click on network settings and then finally 'windows connect now'.
This should transfer the SSID, encryption etc from your pen/flash drive and you should be connected
Hope this works for you