First thing to check when an entire system seems to go out is your fuses. You have a fuse panel in the interior and engine compartment. The interior fuse panel is usually to the lower left of the dash or by the driver's side kick panel (by your left foot). You owner's manual should have instructions on how to find the fuses.
If you replace a fuse and it blows again, there is likely some drawing too much current through the circuit. This could be a shorted light bulb socket or something else. It will need to be checked out if you or a friend is not familiar with electrical.
A bad fuse will look like this: http://www.societyofrobots.com/images/electronics_fuse_blown.jpg
A good fuse will be unbroken: http://www.societyofrobots.com/images/electronics_fuse_not_blown.jpg
If you have more questions, let us know. hope this helps