I was going to say the same as others - you want a development circle or join a private group. You shouldn't have to spend a lot of money to do this, so be careful.
If you are happy in the church you went to, ask in there. They will have open and closed circles for development. You could even try an open circle - this is where everyone goes and everyone is welcome to speak. A lot of it is about having the confidence to say what comes into your mind, which can be very daunting.
I have done this stuff for years, but am still very cynical even though, strangely, I have no reason to be. I've had my own 'proof' lots of times. I don't know why I'm so doubtful, possibly I'm too influenced by others. If you are really interested in this path, ignore what others think or just don't tell them.
Finally, if you want a taste of what it would be like, download a spiritual meditation from Amazon. Something like meeting your spirit guide. That would give you a good idea about the type of exercises you would be doing, although, of course, you wouldn't be able to give messages if you are working alone and that is the big test for people.
Enjoy! 