How to extract a signal received from a given angle by two microphones
Cross correlation is most suitable for low SNR long term observation of continuous signals.  

I recommend you try to identify the leading edges of your short duration received  Signals. Leading edges are usually direct paths. The classic text book solution is to use a matched filter, but often a high Signal level is enough. With the speed of sound and time difference of leading edges, simple geometry should give you an estimate of the direction of arrival.

In actual SONAR a single multi mode  ring hydrophone produces an arrival direction. I don't know if there is a comparable sensor in air acoustics.

You should also try to see if there are built in offsets in your collections. Not all audio cards have actual multichannel sampling.

Good luck