Look in the tray (probably the area on the right end of the taskbar) to see if your networking daemon is there and running. If it isn't, or if you can't tell for sure, try opening a terminal and typing:
That may be enough to get it working, or simply put the applet in the tray where you can configure it. I've seen the applet fail to run by default lately and figured out a workaround rather than investigate why (I'm lazy that way).
If that doesn't do what you need try typing lspci
in the terminal and post the output here so there's information about the hardware that might help figure out what's needed.