I need information on anal fisting, please help.

I've NEVER been fisted and I need to know what it feels like.
Does it feel like a hard cock (or dildo. or strap-on) in your asshole?
Is there enough room to open your fist when it's up my asshole?
What needs to be done before the first time getting fisted?
Enema or what?
Can someone (Male or Female) make me cum by fisting me? [Prostrate massage maybe?]
I've had a few cocks up my ass and none could make me cum just by fucking me.
How does one go about finding someone to fist me? (Male or Female. Hell, a crossdresser/shemale would work.)
I really am serious about this!