Can't get security to work on my wireless network

[Kathyis6incheshigh]

OK so I have bought a wireless router and set up my wireless network and am feeling pretty damn pleased with myself - 'Look at me, I'm Mumsnetting in the garden!' etc.

The trouble is I can't work out how to get security enabled so that it actually asks me for a password on the other computers.
I have set it up on the main computer so it says security is enabled and I have told it a password. When I do this and look on my other computers it shows the connection with a little padlock, along with my neighbours' wireless networks. However, I can't find a way in when it does that - I can't find anywhere where it asks me for a password.

Can anyone help? It's a Belkin router.

TIA....

You set it up exactly the same as you did on the main computer: the 'password' (it is not actually a password in the normal sense, but that doesn't matter at the moment) is set on the router, and is the same for all devices attaching to the wireless network.

Thanks Mr Vibrating - will have a go....