Well you can try activating your card manually?
Open a terminal, become root and do
(assuming your machine's IP is 10.0.0.6 and your gateway is 10.0.0.2)
Code:
/sbin/ifconfig eth0 down
/sbin/ifconfig eth0 10.0.0.6 netmask 255.255.255.0 broadcast 10.254.255.255 up
/sbin/route del default
/sbin/route add default gw 10.0.0.2 eth0
(You can of course put the above lines in /etc/rc.local so that they get executed each time the system starts, and it will thusly come up with the interface already up and running)
I too had problems with the FC11 graphical network management client (I turned it off completely), and this is how I got it working without using the client.
Note that the above does assume that your NIC is working and / or that its module is loaded into the kernel. The fact that you say that the network control app does display it seems to indicate that this is true already, so maybe the above steps will help?