windows vistas help?

welli m trying to set up a wireless network so im told to go to:

start>network>network an sharing center> manage wireless networks

but i dont see the option "manage wireless networks". i found another method:

connect to>set up a connection or network>Manually connect to a wireless network

but there is no option for "Manually connect to a wireless network" seems my new bought vistas computer doesnt have the the option "Manually connect to a wireless network" or other wireless stuff. also, i clicked diagnose and it says a plug is unplugged or my network adapter is not installed? somoene help me find a way to either get the wireless options to show up or something pleasE?
p.s im on a DESKTOP, not a laptop =) if that helps?

if you are on a laptop and its a new upgraded one then you should have wi fi.. there should be a botton or somethin that says wireless on it... i have an hp laptop and its in the front and it slides on or off that should turn it on for you

Do you have a wireless adapter for your computer/laptop? Did it come with one?

First of all, you have to make sure you have a working wireless router/modem set up.

Then, open Network Connections (or whatever it's called) and, assuming there is a wireless lan option, enable it. You can browse for your network from that icon by right-clicking it and asking to show available networks. Or, so it is in XP. Vista messed up a lot of things, so there is no guarantee.

Turn wireless on (button somewhere on your computer), click on the network icon on your taskbar and select Connect to a network. Select the network you wish to connect to and if prompted, enter the passphrase or password.
As said above, make sure you have a working router and modem.
If you have any questions, e-mail me.

PS: Are you on a laptop or desktop? Does it have an integraded wireless card or some kind of adaptor?