Did your HP Pavillion DV5000 come with documentation? I'm sure there is a blue highlighted FN key. That, in combination with another key, should turn devices on or off.
There is a separate button to enable the wireless interface. The button is above the others in the center of the case. When enabled, a ring under the HP logo starts shining blue. It seems to be disabled on the hardware level, that is you can enable/disable it in BIOS, not only from Windows.