Hi you would be better off going to the ubuntu freq asked questions on their forum or you can post a request for help directly on the ubuntu support webpage they are very helpful. Hope that helps my Pc uses ubuntu Natty Narwhal 11.04 wireless and wired no probs its a pre release so can`t comment on back releases sorry.
Yep go through the FAQs but if you don`t get anywhere there is a section to ask for assistance via email (I found them very good at this).
Make sure you have all the latest updates installed and also the restricted drivers installed. Just go to the software centre type "restricted" and install them. There are quite a lot of queries out there if you search on ubuntu and wireless on google etc.
Ubuntu only has support for certain chipsets. Check out "https://help.ubuntu.com/community/WifiDocs/WirelessCardsSupported"
but if it isn't being picked up I wouldn't expect it to work, hardware support is normally pretty good if there are drivers available.
You could try looking at the list and getting a dongle that is supported or alternatively run a cable.