Accessing my Workgroups?

Hi, im relatively new to the network scene. Please could someone assist me?
I have just set up a wireless network with 2 computers. I am just using 2
simple network adapters. I am using freeserve broadband. I can
access the internet from the network but i cannot file or printer share at
the moment. I am using XP and everytime i click on Network places and then
Workgroups it gives the following message.
"You might not have permission to use this network resource. Conatct the
administrator of this server to find out if you have access permissions. The
list of servers for this workgroup are not currently avaliable."
I am logged in as the administrator though, and as far as i can see any
firewall settings are turned off. Does anyone know what i have to do to
access my workgroups so i can file share. This is really annoying me as i
cannot use the netowork to its full potential.
Cheers John