Pulled from a Bee Forum posting (http://www.beesource.com/forums/archive/index.php/t-195408.html) in 2005

I imagine the best way to find feral bees would be to start at a food source.  Or a water source, which has the advantage of being a year-round resource, exploited every flying day. Water sources also tend to be close to the hive.

I just catch 'em, and release 'em with a bee-lining box at different points, and triangulate the hive location from the flight vectors. Its faster than all the mucking about and waiting about just to get a single direction vector and a questionable distance vector, as multiple flight direction vectors, taken far enough apart yield a much more accurate location estimate. Using a GPS to "project a waypoint" at the intersection of the various vectors makes the process even easier.

Catch some foraging bees (3 to dozens) Keep them in the holding chamber of the box long enough to allow them to "fill up" on the fake nectar-soaked sponge. Release a bee, watch it circle, then fly off

Note direction vector, using compass Draw vector on map or project a waypoint on a GPS (depending on which century you live in).  Repeat steps 3 to 5 until the rough hive location becomes obvious, a process
that is made easier by releasing bees at points that are farther apart. Walk at a rough right angle to the last noted direction of flight, and you should be walking a rough arc around the hive location. Searching the general area triangulated for the hive entrance is a matter of listening and watching.

Some want to follow the bee's path and release another bee when they arrive at the spot where
they lost sight of the bee. This is not "triangulation", but it works just as well, as long as you are willing to trust every bee you release, rather than take a more "statistical" view, where no one bee is going to lead you
astray. It is a matter of personal choice and style.