EvilTwins
What sort of things did your DP use to spank you with?
Hand, crop, cane, flogger and a variety of paddles. My favourite is a big heavy wooden paddle we own. I like the feel of wood but it's nice to have a variety.
We broke the crop, actually. It was one supplied by the dungeon. They were fine about it.
How did you discover you liked being spanked?
I think I've always known. I was far too interested in spanking references in Enid Blyton books as a child. And there were frequently stories in "Bunty" and "Nikki" with Victorian orphans getting caned which I read with a lot of interest.
By the time I was a teenager, I was more likely to be thinking about spanking than sex when masturbating.
When I was in my late teens/early twenties, I was too embarrassed to bring it up with partners during sex, though. And then I was celibate for a looong time.
When I started dating again at 40, I knew this was something that I wanted. I had already written a few spanking-based erotic novels by then and met my first spanking partner at an Erotic Authors Conference, so that made it easy to bring into the conversation. 
After fantasising about it for so long, I was a bit worried that I wouldn't enjoy it after all and the whole thing would be an anti-climax. But luckily I enjoyed it as much as I thought I would.