Ideal's SureTest tracer kit is supposed to have a breaker finding mode, along with everything else you might need.
How well it all works I can't say yet, but I have been thinking about getting one.
I have the Sperry and with good batteries it works almost OK. In a non critical environment (don't trip the wrong circuit or else) you can at least use it to kill your circuit with only one walk to the panel. If the first breaker it says is it isn't it, keep trying until the signal dies. Then you know you have the right one.
