In addition..... Were you able to connect to a wireless network before this issue started? Are you using any 3rd party wireless program? Also, you might want to start looking at all Apple programs/apps such as iTunes, bonjour, etc..... sometimes these programs can cause issue.....uninstall them for now during the debugging process and see if this will alleviate your issue. Re-install them back if needed as soon as your issue has been resolved.
We'll appreciate an update.