find_symbol.sh

#!/bin/sh
# First argument: library folder (e.g. /opt/ros/hydro/lib)
# Second argument: mangled symbol (e.g. _ZN14openni_wrapper12OpenNIDevice15getSerialNumberEv)
for lib in $(find $1 -name \*.so) ; do
    res=`nm -D $lib | grep $2 | grep -v " U "`
    if [ ! -z "$res" ]; then
        echo "$lib: $res"
    fi
done

You can also parse the $LD_LIBRARY_PATH to make the first argument optional

@po1: checking the whole $LD_LIBRARY_PATH would be overkill for ROS symbols (this was made for someone with troubles on http://answers.ros.org).