I should say it is extremely simple to connect to internet via WLL (I have a BSNL WLL highspeed connection)
These steps would help you with it :

1. After installing Ubuntu 9.04, connect your WLL equipment (switch it on) to the computer.
2. It Automatically detects it. Right Click on the network icon (on the top right corner) and click “edit connections”
3. Select the “Mobile Broadband” tab.
4. You should now see your connection in it. Just select it and click “Edit”
5. Enter your Username and Password.
6. That’s it… seriously…its so simple…

Just a few weeks earlier, I was desperate to go online using my ubuntu (earlier versions) and then I checked out Jaunty Jackalope the day after it was released. I didn’t find much of a difference, and so I removed it. But today, I just wanted to try it out once more. Now I have started to like it. I must say, “ubuntu is really really cool..”