evans ...

^ Is there a directional antenna that can be used with a handheld
^ scanner ? I'm trying to track down the origin of a signal in my
^ neighborhood.
^
^ Can one be made easily ?

One can be made easily for VHF and UHF, not as easily for other bands.

If the signal you need to locate the origin of is VHF or UHF then make a Yagi
antenna. Since this will be a receive -only antenna you can skip the matching
transformer (or balun) and you can use a simple half-wave dipole instead of a
folded dipole. A few feet of wire, a plastic or wood pole, and a short piece
of any type of coax are all you will need.

Frank