try changing a bulb, maybe a surge blew them.
try measuring power at the circuit breaket output screw inside the
panel with one hand in your pocket and the other handing a few dollars
to a local electrician.
review the faq while waiting for the electrician to arrive at:
http://www.faqs.org/faqs/electrical-wiring/part1/

Mark Modrall wrote:
Hi...

On top of everything else blowing up in the house lately, we had an
odd thing - the circuit which we think has just the garage lights
appears to have gone dead. At least none of the lights come on, and I'd
be skeptical that all the bulbs blew at once. We haven't noticed any
other things being out and the circuit breaker wasn't flipped. We
toggled it a few times just to be sure, but no luck.

What should we look at first, or should we just call the electrician?

Thanks
-Mark