I had some trouble with my wireless also, but it's now sorted out, big thanks goes to chili555: ipw2200 problems in Hardy, Acer Aspire 1690
I was lucky, because it took just a couple of days.
On the Networking & Wireless page there are 2 sticky threads (at the time of writing).
One of them is Supported wireless cards list and procedure to get help. -> There is a link HOWTO post a Wireless issue (ticket) by gnusci.
I would recommend that you attach the outputs of those commands in the terminal in your post, as I did it in my thread.
These are the commands I meant:
1 ) Machine Brand and Model (PC/Laptop):
2 ) Wireless Brand, Model and Wireless Chipset:
Get it from your product information.
(hint) use grep to get only information about the Wireless
3 ) check interface:
$ lspci -nn | grep 'Wireless Brand'
(hint) if the Wireless interface name is wlan0 you can also use
4 ) Check for modules:
(hint) search for the Wireless module
5 ) Kernel boot messages
$ lsmod | grep "wlan_module_name"
(hint) the same as in (4)
6 ) Network configuration
7 ) Scan for networks:
$ sudo lshw -C network
(hint) the same as in (3)
8 ) Ubuntu Version:
$ iwlist scan wlan0
9 ) Kernel/architecture (including 32 vs. 64 bit):
10 ) Restarting the network:
END OF EDIT
$ sudo /etc/init.d/networking restart
It would help others to see what's wrong exactly.
Don't forget to describe your issue also.
Good luck fixing your problems.