There are better ways to communicate with them, and the ghosts around here don't seem to be the kind that are able to communicate easily with us as it is. I've tried. They're more...echoes, of what the people used to be.

You don't. At best, you'll get a prankster-type spirit having fun with you, at worst, you make it easier for less nice things to communicate.

Believe me, you're not the only one who'd like to try and find out what happened. If you're serious, and not just in it for laughs, I'll take you ghost-hunting when things are 'normal' again.