Again, I am ever wary of something unknown, simply because the otherworld contains power and influence completely unfathomable to us humans. You don't want to pick up a 'nasty' who could exploit you for its own needs. I don't disagree with contacting dead friends or loved ones, but nor do I agree with it. If there is understanding or resolution that you are searching for, it will come to you when you are ready. There are many ways, my advice is to not try to influence anything but yourself.
Faith is a very powerful thing.
I've read books about mediums and channels and, really, it is not always very much fun. It explains a lot of the strange shifts in my life, and I am at peace with my belief. Keep a pad and flashlight next to the bed. Write down all the dreams you can remember as soon as you wake up. I wasn't sure if it would.