cm9 does not support ad-hoc because ics doen not provide that facility. But we can create a virtual router and share the wifi from our laptop.
1.Download virtual router(you can google it. version:0.9 beta).
2.Install it in your system.Open it.
3.Now open command promt as administrator and type this
netsh wlan set hostednetwork mode=allow ssid=android key=TYPE YOUR PASSWORD
4.Type netsh wlan start hostednetwork and press enter. Now you hava created a virtual router.
5.Open network and sharing center. it will display your lan network which is connected to internet.
6.Click on Local area connection and select properties. A new window will open.
7.Select sharing from that window. There will be something called Allow network users to connect through this computer's internet. Click on the Checkbox.
8.Select the network. Usually it will be wireless network connection 2. If not select wireless network connection.
9.Hit ok. Now you will be able to share your internet connection via wifi.
ANY BROKEN LINKS!! PLEASE REPORT.