It appears one of the updates to the linpus linux operating system used on Asus Aspire One netbooks messes up the networking. In short the permissions get set wrongly on the network settings files. Symptons include, not being able to see the network icon on the menu, clicking "Network Settings" icon on the settings page and having nothing happen etc..
Before you run this fix, please understand that you will lose all your saved network connections and you will need to add in your network keys again.
To fix:
Press Alt+F2 and a run box should appear.
Then write "terminal" and click "Run".
In the new terminal windows that has appeared type "sudo gconftool-2 --recursive-unset /system/networking" to clear all the root network connections.
Then type "gconftool-2 --recursive-unset /system/networking" to clear all the user network connections.
Reboot the netbook and the network icon appears again after about 20 seconds but you need to reconfigure the network connections again by adding passwords etc...
If this hasn't fixed your problem then this forum has loads more info on the subject
http://www.aspireoneuser.com/forum/viewtopic.php?f=34&t=2620&sid=7ee9a1caf5a8ccaf10dd281ac6caf861. I recommend reading the whole forum thread before trying the solutions, as you may want to try easier ones first!
Acer Aspire One Linpus